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<li><a class="reference internal" href="#"><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code> --- 基本日期和时间类型</a><ul>
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<li><a class="reference internal" href="#aware-and-naive-objects">感知型对象和简单型对象</a></li>
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<section id="module-datetime">
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<span id="datetime-basic-date-and-time-types"></span><h1><a class="reference internal" href="#module-datetime" title="datetime: Basic date and time types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code></a> --- 基本日期和时间类型<a class="headerlink" href="#module-datetime" title="永久链接至标题">¶</a></h1>
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<p><strong>源代码：</strong> <a class="reference external" href="https://github.com/python/cpython/tree/3.8/Lib/datetime.py">Lib/datetime.py</a></p>
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<p><a class="reference internal" href="#module-datetime" title="datetime: Basic date and time types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code></a> 模块提供用于处理日期和时间的类。</p>
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<p>在支持日期时间数学运算的同时，实现的关注点更着重于如何能够更有效地解析其属性用于格式化输出和数据操作。</p>
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<dt>模块 <a class="reference internal" href="calendar.html#module-calendar" title="calendar: Functions for working with calendars, including some emulation of the Unix cal program."><code class="xref py py-mod docutils literal notranslate"><span class="pre">calendar</span></code></a></dt><dd><p>通用日历相关函数</p>
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<dt><a class="reference external" href="https://dateutil.readthedocs.io/en/stable/">dateutil</a> 包</dt><dd><p>具有扩展时区和解析支持的第三方库。</p>
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<section id="aware-and-naive-objects">
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<span id="datetime-naive-aware"></span><h2>感知型对象和简单型对象<a class="headerlink" href="#aware-and-naive-objects" title="永久链接至标题">¶</a></h2>
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<p>日期和时间对象可以根据它们是否包含时区信息而分为“感知型”和“简单型”两类。</p>
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<p>充分掌握应用性算法和政治性时间调整信息例如时区和夏令时的情况下，一个 <strong>感知型</strong> 对象就能相对于其他感知型对象来精确定位自身时间点。 感知型对象是用来表示一个没有解释空间的固定时间点。 <a class="footnote-reference brackets" href="#id5" id="id1">1</a></p>
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<p><strong>简单型</strong> 对象没有包含足够多的信息来无歧义地相对于其他 date/time 对象来定位自身时间点。 不论一个简单型对象所代表的是世界标准时间（UTC）、当地时间还是某个其他时区的时间完全取决于具体程序，就像一个特定数字所代表的是米、英里还是质量完全取决于具体程序一样。 简单型对象更易于理解和使用，代价则是忽略了某些现实性考量。</p>
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<p>对于要求感知型对象的应用，<a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 和 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象具有一个可选的时区信息属性 <code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code>，它可被设为抽象类 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 的子类的一个实例。 这些 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 对象会捕获与 UTC 时间的差值、时区名称以及夏令时是否生效等信息。</p>
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<p><a class="reference internal" href="#module-datetime" title="datetime: Basic date and time types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code></a> 模块只提供了一个具体的 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 类，即 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 类。 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 类可以表示具有相对于 UTC 的固定时差的简单时区，例如 UTC 本身或北美的 EST 和 EDT 时区等。 支持时间的详细程度取决于具体的应用。 世界各地的时间调整规则往往是政治性多于合理性，经常会发生变化，除了 UTC 之外并没有一个能适合所有应用的标准。</p>
|
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</section>
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<section id="constants">
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<h2>常量<a class="headerlink" href="#constants" title="永久链接至标题">¶</a></h2>
|
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<p>The <a class="reference internal" href="#module-datetime" title="datetime: Basic date and time types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code></a> module exports the following constants:</p>
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<dl class="data">
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<dt id="datetime.MINYEAR">
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<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">MINYEAR</code><a class="headerlink" href="#datetime.MINYEAR" title="永久链接至目标">¶</a></dt>
|
||
<dd><p><a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 或者 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象允许的最小年份。 常量 <a class="reference internal" href="#datetime.MINYEAR" title="datetime.MINYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MINYEAR</span></code></a> 是 <code class="docutils literal notranslate"><span class="pre">1</span></code> 。</p>
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</dd></dl>
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<dl class="data">
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<dt id="datetime.MAXYEAR">
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<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">MAXYEAR</code><a class="headerlink" href="#datetime.MAXYEAR" title="永久链接至目标">¶</a></dt>
|
||
<dd><p><a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 或 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象允许最大的年份。常量 <a class="reference internal" href="#datetime.MAXYEAR" title="datetime.MAXYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MAXYEAR</span></code></a> 是 <code class="docutils literal notranslate"><span class="pre">9999</span></code> 。</p>
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||
</dd></dl>
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||
|
||
</section>
|
||
<section id="available-types">
|
||
<h2>有效的类型<a class="headerlink" href="#available-types" title="永久链接至标题">¶</a></h2>
|
||
<dl class="class">
|
||
<dt>
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">date</code></dt>
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<dd><p>一个理想化的简单型日期，它假设当今的公历在过去和未来永远有效。 属性: <a class="reference internal" href="#datetime.date.year" title="datetime.date.year"><code class="xref py py-attr docutils literal notranslate"><span class="pre">year</span></code></a>, <a class="reference internal" href="#datetime.date.month" title="datetime.date.month"><code class="xref py py-attr docutils literal notranslate"><span class="pre">month</span></code></a>, and <a class="reference internal" href="#datetime.date.day" title="datetime.date.day"><code class="xref py py-attr docutils literal notranslate"><span class="pre">day</span></code></a>。</p>
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</dd></dl>
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<dl class="class">
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<dt>
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<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">time</code></dt>
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<dd><p>一个独立于任何特定日期的理想化时间，它假设每一天都恰好等于 24*60*60 秒。 （这里没有“闰秒”的概念。） 包含属性: <a class="reference internal" href="#datetime.time.hour" title="datetime.time.hour"><code class="xref py py-attr docutils literal notranslate"><span class="pre">hour</span></code></a>, <a class="reference internal" href="#datetime.time.minute" title="datetime.time.minute"><code class="xref py py-attr docutils literal notranslate"><span class="pre">minute</span></code></a>, <a class="reference internal" href="#datetime.time.second" title="datetime.time.second"><code class="xref py py-attr docutils literal notranslate"><span class="pre">second</span></code></a>, <a class="reference internal" href="#datetime.time.microsecond" title="datetime.time.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 和 <a class="reference internal" href="#datetime.time.tzinfo" title="datetime.time.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a>。</p>
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</dd></dl>
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<dl class="class">
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||
<dt>
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">datetime</code></dt>
|
||
<dd><p>日期和时间的结合。属性：<a class="reference internal" href="#datetime.datetime.year" title="datetime.datetime.year"><code class="xref py py-attr docutils literal notranslate"><span class="pre">year</span></code></a>, <a class="reference internal" href="#datetime.datetime.month" title="datetime.datetime.month"><code class="xref py py-attr docutils literal notranslate"><span class="pre">month</span></code></a>, <a class="reference internal" href="#datetime.datetime.day" title="datetime.datetime.day"><code class="xref py py-attr docutils literal notranslate"><span class="pre">day</span></code></a>, <a class="reference internal" href="#datetime.datetime.hour" title="datetime.datetime.hour"><code class="xref py py-attr docutils literal notranslate"><span class="pre">hour</span></code></a>, <a class="reference internal" href="#datetime.datetime.minute" title="datetime.datetime.minute"><code class="xref py py-attr docutils literal notranslate"><span class="pre">minute</span></code></a>, <a class="reference internal" href="#datetime.datetime.second" title="datetime.datetime.second"><code class="xref py py-attr docutils literal notranslate"><span class="pre">second</span></code></a>, <a class="reference internal" href="#datetime.datetime.microsecond" title="datetime.datetime.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a>, and <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a>.</p>
|
||
</dd></dl>
|
||
|
||
<dl class="class">
|
||
<dt>
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">timedelta</code></dt>
|
||
<dd><p>表示两个 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象或 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象，或者 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象之间的时间间隔，精确到微秒。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="class">
|
||
<dt>
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">tzinfo</code></dt>
|
||
<dd><p>一个描述时区信息对象的抽象基类。 用来给 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 和 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 类提供自定义的时间调整概念（例如处理时区和/或夏令时）。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="class">
|
||
<dt>
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">timezone</code></dt>
|
||
<dd><p>一个实现了 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 抽象基类的子类，用于表示相对于 世界标准时间（UTC）的偏移量。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.2 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<p>这些类型的对象都是不可变的。</p>
|
||
<p>子类关系</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="nb">object</span>
|
||
<span class="n">timedelta</span>
|
||
<span class="n">tzinfo</span>
|
||
<span class="n">timezone</span>
|
||
<span class="n">time</span>
|
||
<span class="n">date</span>
|
||
<span class="n">datetime</span>
|
||
</pre></div>
|
||
</div>
|
||
<section id="common-properties">
|
||
<h3>通用的特征属性<a class="headerlink" href="#common-properties" title="永久链接至标题">¶</a></h3>
|
||
<p><a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a>, <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a>, <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 和 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 类型共享这些通用特性:</p>
|
||
<ul class="simple">
|
||
<li><p>这些类型的对象都是不可变的。</p></li>
|
||
<li><p>这些类型的对象是可哈希的，这意味着它们可被作为字典的键。</p></li>
|
||
<li><p>这些类型的对象支持通过 <a class="reference internal" href="pickle.html#module-pickle" title="pickle: Convert Python objects to streams of bytes and back."><code class="xref py py-mod docutils literal notranslate"><span class="pre">pickle</span></code></a> 模块进行高效的封存。</p></li>
|
||
</ul>
|
||
</section>
|
||
<section id="determining-if-an-object-is-aware-or-naive">
|
||
<h3>确定一个对象是感知型还是简单型<a class="headerlink" href="#determining-if-an-object-is-aware-or-naive" title="永久链接至标题">¶</a></h3>
|
||
<p><a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 类型的对象都是简单型的。</p>
|
||
<p><a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 或 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 类型的对象可以是感知型或者简单型。</p>
|
||
<p>一个 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象 <em>d</em> 在以下条件同时成立时将是感知型的：</p>
|
||
<ol class="arabic simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">d.tzinfo</span></code> 不为 <code class="docutils literal notranslate"><span class="pre">None</span></code></p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">d.tzinfo.utcoffset(d)</span></code> 不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code></p></li>
|
||
</ol>
|
||
<p>在其他情况下，<em>d</em> 将是简单型的。</p>
|
||
<p>一个 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象 <em>t</em> 在以下条件同时成立时将是感知型的：</p>
|
||
<ol class="arabic simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">t.tzinfo</span></code> 不为 <code class="docutils literal notranslate"><span class="pre">None</span></code></p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">t.tzinfo.utcoffset(None)</span></code> 不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p></li>
|
||
</ol>
|
||
<p>在其他情况下，<em>t</em> 将是简单型的。</p>
|
||
<p>感知型和简单型之间的区别不适用于 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象。</p>
|
||
</section>
|
||
</section>
|
||
<section id="timedelta-objects">
|
||
<span id="datetime-timedelta"></span><h2><a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 类对象<a class="headerlink" href="#timedelta-objects" title="永久链接至标题">¶</a></h2>
|
||
<p><a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象表示两个 date 或者 time 的时间间隔。</p>
|
||
<dl class="class">
|
||
<dt id="datetime.timedelta">
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">timedelta</code><span class="sig-paren">(</span><em class="sig-param">days=0</em>, <em class="sig-param">seconds=0</em>, <em class="sig-param">microseconds=0</em>, <em class="sig-param">milliseconds=0</em>, <em class="sig-param">minutes=0</em>, <em class="sig-param">hours=0</em>, <em class="sig-param">weeks=0</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.timedelta" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>所有参数都是可选的并且默认为 <code class="docutils literal notranslate"><span class="pre">0</span></code>。 这些参数可以是整数或者浮点数，也可以是正数或者负数。</p>
|
||
<p>只有 <em>days</em>, <em>seconds</em> 和 <em>microseconds</em> 会存储在内部。 参数单位的换算规则如下：</p>
|
||
<ul class="simple">
|
||
<li><p>1毫秒会转换成1000微秒。</p></li>
|
||
<li><p>1分钟会转换成60秒。</p></li>
|
||
<li><p>1小时会转换成3600秒。</p></li>
|
||
<li><p>1星期会转换成7天。</p></li>
|
||
</ul>
|
||
<p>日期、秒、微秒都是标准化的，所以它们的表达方式也是唯一的，例：</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">microseconds</span> <span class="pre"><</span> <span class="pre">1000000</span></code></p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">seconds</span> <span class="pre"><</span> <span class="pre">3600*24</span></code> (一天的秒数)</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">-999999999</span> <span class="pre"><=</span> <span class="pre">days</span> <span class="pre"><=</span> <span class="pre">999999999</span></code></p></li>
|
||
</ul>
|
||
<p>下面的例子演示了如何对 <em>days</em>, <em>seconds</em> 和 <em>microseconds</em> 以外的任意参数执行“合并”操作并标准化为以上三个结果属性:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">timedelta</span>
|
||
<span class="gp">>>> </span><span class="n">delta</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span>
|
||
<span class="gp">... </span> <span class="n">days</span><span class="o">=</span><span class="mi">50</span><span class="p">,</span>
|
||
<span class="gp">... </span> <span class="n">seconds</span><span class="o">=</span><span class="mi">27</span><span class="p">,</span>
|
||
<span class="gp">... </span> <span class="n">microseconds</span><span class="o">=</span><span class="mi">10</span><span class="p">,</span>
|
||
<span class="gp">... </span> <span class="n">milliseconds</span><span class="o">=</span><span class="mi">29000</span><span class="p">,</span>
|
||
<span class="gp">... </span> <span class="n">minutes</span><span class="o">=</span><span class="mi">5</span><span class="p">,</span>
|
||
<span class="gp">... </span> <span class="n">hours</span><span class="o">=</span><span class="mi">8</span><span class="p">,</span>
|
||
<span class="gp">... </span> <span class="n">weeks</span><span class="o">=</span><span class="mi">2</span>
|
||
<span class="gp">... </span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="c1"># Only days, seconds, and microseconds remain</span>
|
||
<span class="gp">>>> </span><span class="n">delta</span>
|
||
<span class="go">datetime.timedelta(days=64, seconds=29156, microseconds=10)</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>在有任何参数为浮点型并且 microseconds 值为小数的情况下，从所有参数中余下的微秒数将被合并，并使用四舍五入偶不入奇的规则将总计值舍入到最接近的整数微秒值。 如果没有任何参数为浮点型的情况下，则转换和标准化过程将是完全精确的（不会丢失信息）。</p>
|
||
<p>如果标准化后的 days 数值超过了指定范围，将会抛出 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a> 异常。</p>
|
||
<p>请注意对负数值进行标准化的结果可能会令人感到惊讶。 例如:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">timedelta</span>
|
||
<span class="gp">>>> </span><span class="n">d</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">microseconds</span><span class="o">=-</span><span class="mi">1</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="p">(</span><span class="n">d</span><span class="o">.</span><span class="n">days</span><span class="p">,</span> <span class="n">d</span><span class="o">.</span><span class="n">seconds</span><span class="p">,</span> <span class="n">d</span><span class="o">.</span><span class="n">microseconds</span><span class="p">)</span>
|
||
<span class="go">(-1, 86399, 999999)</span>
|
||
</pre></div>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<p>类属性：</p>
|
||
<dl class="attribute">
|
||
<dt id="datetime.timedelta.min">
|
||
<code class="sig-prename descclassname">timedelta.</code><code class="sig-name descname">min</code><a class="headerlink" href="#datetime.timedelta.min" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>The most negative <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> object, <code class="docutils literal notranslate"><span class="pre">timedelta(-999999999)</span></code>.</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.timedelta.max">
|
||
<code class="sig-prename descclassname">timedelta.</code><code class="sig-name descname">max</code><a class="headerlink" href="#datetime.timedelta.max" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>The most positive <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> object, <code class="docutils literal notranslate"><span class="pre">timedelta(days=999999999,</span>
|
||
<span class="pre">hours=23,</span> <span class="pre">minutes=59,</span> <span class="pre">seconds=59,</span> <span class="pre">microseconds=999999)</span></code>.</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.timedelta.resolution">
|
||
<code class="sig-prename descclassname">timedelta.</code><code class="sig-name descname">resolution</code><a class="headerlink" href="#datetime.timedelta.resolution" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>两个不相等的 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 类对象最小的间隔为 <code class="docutils literal notranslate"><span class="pre">timedelta(microseconds=1)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<p>需要注意的是，因为标准化的缘故，<code class="docutils literal notranslate"><span class="pre">timedelta.max</span></code> > <code class="docutils literal notranslate"><span class="pre">-timedelta.min</span></code>，<code class="docutils literal notranslate"><span class="pre">-timedelta.max</span></code> 不可以表示一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 类对象。</p>
|
||
<p>实例属性（只读）：</p>
|
||
<table class="docutils align-default">
|
||
<colgroup>
|
||
<col style="width: 29%" />
|
||
<col style="width: 71%" />
|
||
</colgroup>
|
||
<thead>
|
||
<tr class="row-odd"><th class="head"><p>属性</p></th>
|
||
<th class="head"><p>值</p></th>
|
||
</tr>
|
||
</thead>
|
||
<tbody>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">days</span></code></p></td>
|
||
<td><p>-999999999 至 999999999 ，含999999999</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">seconds</span></code></p></td>
|
||
<td><p>0 至 86399，包含86399</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">microseconds</span></code></p></td>
|
||
<td><p>0 至 999999，包含999999</p></td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
<p>支持的运算：</p>
|
||
<table class="docutils align-default">
|
||
<colgroup>
|
||
<col style="width: 41%" />
|
||
<col style="width: 59%" />
|
||
</colgroup>
|
||
<thead>
|
||
<tr class="row-odd"><th class="head"><p>运算</p></th>
|
||
<th class="head"><p>结果：</p></th>
|
||
</tr>
|
||
</thead>
|
||
<tbody>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">t1</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">+</span> <span class="pre">t3</span></code></p></td>
|
||
<td><p><em>t2</em> 和 <em>t3</em> 的和。 运算后 <em>t1</em>-<em>t2</em> == <em>t3</em> and <em>t1</em>-<em>t3</em> == <em>t2</em> 必为真值。(1)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">t1</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">-</span> <span class="pre">t3</span></code></p></td>
|
||
<td><p><em>t2</em> 减 <em>t3</em> 的差。 运算后 <em>t1</em> == <em>t2</em> - <em>t3</em> and <em>t2</em> == <em>t1</em> + <em>t3</em> 必为真值。 (1)(6)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">t1</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">*</span> <span class="pre">i</span> <span class="pre">or</span> <span class="pre">t1</span> <span class="pre">=</span> <span class="pre">i</span> <span class="pre">*</span> <span class="pre">t2</span></code></p></td>
|
||
<td><p>乘以一个整数。运算后假如 <code class="docutils literal notranslate"><span class="pre">i</span> <span class="pre">!=</span> <span class="pre">0</span></code> 则 <em>t1</em> // i == <em>t2</em> 必为真值。</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td></td>
|
||
<td><p>In general, <em>t1</em> * i == <em>t1</em> * (i-1) + <em>t1</em>
|
||
is true. (1)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">t1</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">*</span> <span class="pre">f</span> <span class="pre">or</span> <span class="pre">t1</span> <span class="pre">=</span> <span class="pre">f</span> <span class="pre">*</span> <span class="pre">t2</span></code></p></td>
|
||
<td><p>乘以一个浮点数，结果会被舍入到 timedelta 最接近的整数倍。 精度使用四舍五偶入奇不入规则。</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">f</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">/</span> <span class="pre">t3</span></code></p></td>
|
||
<td><p>总时间 <em>t2</em> 除以间隔单位 <em>t3</em> (3)。 返回一个 <a class="reference internal" href="functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate"><span class="pre">float</span></code></a> 对象。</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">t1</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">/</span> <span class="pre">f</span> <span class="pre">or</span> <span class="pre">t1</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">/</span> <span class="pre">i</span></code></p></td>
|
||
<td><p>除以一个浮点数或整数。 结果会被舍入到 timedelta 最接近的整数倍。 精度使用四舍五偶入奇不入规则。</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">t1</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">//</span> <span class="pre">i</span></code> or
|
||
<code class="docutils literal notranslate"><span class="pre">t1</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">//</span> <span class="pre">t3</span></code></p></td>
|
||
<td><p>计算底数，其余部分（如果有）将被丢弃。在第二种情况下，将返回整数。 （3）</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">t1</span> <span class="pre">=</span> <span class="pre">t2</span> <span class="pre">%</span> <span class="pre">t3</span></code></p></td>
|
||
<td><p>余数为一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象。(3)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">q,</span> <span class="pre">r</span> <span class="pre">=</span> <span class="pre">divmod(t1,</span> <span class="pre">t2)</span></code></p></td>
|
||
<td><p>通过 : <code class="docutils literal notranslate"><span class="pre">q</span> <span class="pre">=</span> <span class="pre">t1</span> <span class="pre">//</span> <span class="pre">t2</span></code> (3) and <code class="docutils literal notranslate"><span class="pre">r</span> <span class="pre">=</span> <span class="pre">t1</span> <span class="pre">%</span> <span class="pre">t2</span></code> 计算出商和余数。q是一个整数，r是一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象。</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">+t1</span></code></p></td>
|
||
<td><p>返回一个相同数值的 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象。</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">-t1</span></code></p></td>
|
||
<td><p>等价于 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a>(-<em>t1.days</em>, -<em>t1.seconds</em>, -<em>t1.microseconds</em>), 和 <em>t1</em>* -1. (1)(4)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">abs(t)</span></code></p></td>
|
||
<td><p>当 <code class="docutils literal notranslate"><span class="pre">t.days</span> <span class="pre">>=</span> <span class="pre">0</span></code> 时等于 +<em>t</em>, 当 <code class="docutils literal notranslate"><span class="pre">t.days</span> <span class="pre"><</span> <span class="pre">0</span></code> 时 -<em>t</em> 。 (2)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">str(t)</span></code></p></td>
|
||
<td><p>返回一个形如 <code class="docutils literal notranslate"><span class="pre">[D</span> <span class="pre">day[s],</span> <span class="pre">][H]H:MM:SS[.UUUUUU]</span></code> 的字符串，当 <code class="docutils literal notranslate"><span class="pre">t</span></code> 为负数的时候， D 也为负数。 (5)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">repr(t)</span></code></p></td>
|
||
<td><p>返回一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象的字符串表示形式，作为附带正规属性值的构造器调用。</p></td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
<p>注释：</p>
|
||
<ol class="arabic">
|
||
<li><p>结果正确，但可能会溢出。</p></li>
|
||
<li><p>结果正确，不会溢出。</p></li>
|
||
<li><p>除以0将会抛出异常 <a class="reference internal" href="exceptions.html#ZeroDivisionError" title="ZeroDivisionError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ZeroDivisionError</span></code></a> 。</p></li>
|
||
<li><p>-<em>timedelta.max</em> 不是一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 类对象。</p></li>
|
||
<li><p><a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象的字符串表示形式类似于其内部表示形式被规范化。对于负时间增量，这会导致一些不寻常的结果。例如:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=-</span><span class="mi">5</span><span class="p">)</span>
|
||
<span class="go">datetime.timedelta(days=-1, seconds=68400)</span>
|
||
<span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="n">_</span><span class="p">)</span>
|
||
<span class="go">-1 day, 19:00:00</span>
|
||
</pre></div>
|
||
</div>
|
||
</li>
|
||
<li><p>表达式 <code class="docutils literal notranslate"><span class="pre">t2</span> <span class="pre">-</span> <span class="pre">t3</span></code> 通常与 <code class="docutils literal notranslate"><span class="pre">t2</span> <span class="pre">+</span> <span class="pre">(-t3)</span></code> 是等价的，除非 t3 等于 <code class="docutils literal notranslate"><span class="pre">timedelta.max</span></code>; 在这种情况下前者会返回结果，而后者则会溢出。</p></li>
|
||
</ol>
|
||
<p>除了上面列举的操作以外，<a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象还支持与 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 和 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象进行特定的相加和相减运算（见下文）。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.2 版更改: </span>现在已支持 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象与另一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象相整除或相除，包括求余运算和 <a class="reference internal" href="functions.html#divmod" title="divmod"><code class="xref py py-func docutils literal notranslate"><span class="pre">divmod()</span></code></a> 函数。 现在也支持 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象加上或乘以一个 <a class="reference internal" href="functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate"><span class="pre">float</span></code></a> 对象。</p>
|
||
</div>
|
||
<p>支持 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象之间进行比较，但其中有一些注意事项。</p>
|
||
<p><code class="docutils literal notranslate"><span class="pre">==</span></code> 或 <code class="docutils literal notranslate"><span class="pre">!=</span></code> 比较 <em>总是</em> 返回一个 <a class="reference internal" href="functions.html#bool" title="bool"><code class="xref py py-class docutils literal notranslate"><span class="pre">bool</span></code></a> 对象，无论被比较的对象是什么类型:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">timedelta</span>
|
||
<span class="gp">>>> </span><span class="n">delta1</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">seconds</span><span class="o">=</span><span class="mi">57</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">delta2</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">25</span><span class="p">,</span> <span class="n">seconds</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">delta2</span> <span class="o">!=</span> <span class="n">delta1</span>
|
||
<span class="go">True</span>
|
||
<span class="gp">>>> </span><span class="n">delta2</span> <span class="o">==</span> <span class="mi">5</span>
|
||
<span class="go">False</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>对于所有其他比较 (例如 <code class="docutils literal notranslate"><span class="pre"><</span></code> 和 <code class="docutils literal notranslate"><span class="pre">></span></code>)，当一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象与其他类型的对象比较时，将引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">delta2</span> <span class="o">></span> <span class="n">delta1</span>
|
||
<span class="go">True</span>
|
||
<span class="gp">>>> </span><span class="n">delta2</span> <span class="o">></span> <span class="mi">5</span>
|
||
<span class="gt">Traceback (most recent call last):</span>
|
||
File <span class="nb">"<stdin>"</span>, line <span class="m">1</span>, in <span class="n"><module></span>
|
||
<span class="gr">TypeError</span>: <span class="n">'>' not supported between instances of 'datetime.timedelta' and 'int'</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>在布尔运算中，<a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象当且仅当其不等于 <code class="docutils literal notranslate"><span class="pre">timedelta(0)</span></code> 时则会被视为真值。</p>
|
||
<p>实例方法：</p>
|
||
<dl class="method">
|
||
<dt id="datetime.timedelta.total_seconds">
|
||
<code class="sig-prename descclassname">timedelta.</code><code class="sig-name descname">total_seconds</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.timedelta.total_seconds" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回期间占用了多少秒。等价于 <code class="docutils literal notranslate"><span class="pre">td</span> <span class="pre">/</span> <span class="pre">timedelta(seconds=1)</span></code>。对于秒以外的间隔单位，直接使用除法形式 (例如 <code class="docutils literal notranslate"><span class="pre">td</span> <span class="pre">/</span> <span class="pre">timedelta(microseconds=1)</span></code>)。</p>
|
||
<p>需要注意的是，时间间隔较大时，这个方法的结果中的微秒将会失真（大多数平台上大于270年视为一个较大的时间间隔）。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.2 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<section id="examples-of-usage-timedelta">
|
||
<h3><a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 用法示例<a class="headerlink" href="#examples-of-usage-timedelta" title="永久链接至标题">¶</a></h3>
|
||
<p>一个标准化的附加示例:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="c1"># Components of another_year add up to exactly 365 days</span>
|
||
<span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">timedelta</span>
|
||
<span class="gp">>>> </span><span class="n">year</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">days</span><span class="o">=</span><span class="mi">365</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">another_year</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">weeks</span><span class="o">=</span><span class="mi">40</span><span class="p">,</span> <span class="n">days</span><span class="o">=</span><span class="mi">84</span><span class="p">,</span> <span class="n">hours</span><span class="o">=</span><span class="mi">23</span><span class="p">,</span>
|
||
<span class="gp">... </span> <span class="n">minutes</span><span class="o">=</span><span class="mi">50</span><span class="p">,</span> <span class="n">seconds</span><span class="o">=</span><span class="mi">600</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">year</span> <span class="o">==</span> <span class="n">another_year</span>
|
||
<span class="go">True</span>
|
||
<span class="gp">>>> </span><span class="n">year</span><span class="o">.</span><span class="n">total_seconds</span><span class="p">()</span>
|
||
<span class="go">31536000.0</span>
|
||
</pre></div>
|
||
</div>
|
||
<p><a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 算术运算的示例:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">timedelta</span>
|
||
<span class="gp">>>> </span><span class="n">year</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">days</span><span class="o">=</span><span class="mi">365</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">ten_years</span> <span class="o">=</span> <span class="mi">10</span> <span class="o">*</span> <span class="n">year</span>
|
||
<span class="gp">>>> </span><span class="n">ten_years</span>
|
||
<span class="go">datetime.timedelta(days=3650)</span>
|
||
<span class="gp">>>> </span><span class="n">ten_years</span><span class="o">.</span><span class="n">days</span> <span class="o">//</span> <span class="mi">365</span>
|
||
<span class="go">10</span>
|
||
<span class="gp">>>> </span><span class="n">nine_years</span> <span class="o">=</span> <span class="n">ten_years</span> <span class="o">-</span> <span class="n">year</span>
|
||
<span class="gp">>>> </span><span class="n">nine_years</span>
|
||
<span class="go">datetime.timedelta(days=3285)</span>
|
||
<span class="gp">>>> </span><span class="n">three_years</span> <span class="o">=</span> <span class="n">nine_years</span> <span class="o">//</span> <span class="mi">3</span>
|
||
<span class="gp">>>> </span><span class="n">three_years</span><span class="p">,</span> <span class="n">three_years</span><span class="o">.</span><span class="n">days</span> <span class="o">//</span> <span class="mi">365</span>
|
||
<span class="go">(datetime.timedelta(days=1095), 3)</span>
|
||
</pre></div>
|
||
</div>
|
||
</section>
|
||
</section>
|
||
<section id="date-objects">
|
||
<span id="datetime-date"></span><h2><a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象<a class="headerlink" href="#date-objects" title="永久链接至标题">¶</a></h2>
|
||
<p><a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象代表一个理想化历法中的日期（年、月和日），即当今的格列高利历向前后两个方向无限延伸。</p>
|
||
<p>公元 1 年 1 月 1日是第 1 日，公元 1 年 1 月 2 日是第 2 日，依此类推。 <a class="footnote-reference brackets" href="#id6" id="id2">2</a></p>
|
||
<dl class="class">
|
||
<dt id="datetime.date">
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">date</code><span class="sig-paren">(</span><em class="sig-param">year</em>, <em class="sig-param">month</em>, <em class="sig-param">day</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>所有参数都是必要的。 参数必须是在下面范围内的整数：</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">MINYEAR</span> <span class="pre"><=</span> <span class="pre">year</span> <span class="pre"><=</span> <span class="pre">MAXYEAR</span></code></p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">1</span> <span class="pre"><=</span> <span class="pre">month</span> <span class="pre"><=</span> <span class="pre">12</span></code></p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">1</span> <span class="pre"><=</span> <span class="pre">日期</span> <span class="pre"><=</span> <span class="pre">给定年月对应的天数</span></code></p></li>
|
||
</ul>
|
||
<p>如果参数不在这些范围内，则抛出 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a> 异常。</p>
|
||
</dd></dl>
|
||
|
||
<p>其它构造器，所有的类方法：</p>
|
||
<dl class="method">
|
||
<dt id="datetime.date.today">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">date.</code><code class="sig-name descname">today</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.today" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回当前的本地日期。</p>
|
||
<p>这等价于 <code class="docutils literal notranslate"><span class="pre">date.fromtimestamp(time.time())</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.fromtimestamp">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">date.</code><code class="sig-name descname">fromtimestamp</code><span class="sig-paren">(</span><em class="sig-param">timestamp</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.fromtimestamp" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回对应于 POSIX 时间戳的当地时间，例如 <a class="reference internal" href="time.html#time.time" title="time.time"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.time()</span></code></a> 返回的就是时间戳。</p>
|
||
<p>这可能引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a>，如果时间戳数值超出所在平台 C <code class="xref c c-func docutils literal notranslate"><span class="pre">localtime()</span></code> 函数的支持范围的话，并且会在 <code class="xref c c-func docutils literal notranslate"><span class="pre">localtime()</span></code> 出错时引发 <a class="reference internal" href="exceptions.html#OSError" title="OSError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OSError</span></code></a>。 通常该数值会被限制在 1970 年至 2038 年之间。 请注意在时间戳概念包含闰秒的非 POSIX 系统上，闰秒会被 <a class="reference internal" href="#datetime.date.fromtimestamp" title="datetime.date.fromtimestamp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromtimestamp()</span></code></a> 所忽略。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.3 版更改: </span>引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a> 而不是 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>，如果时间戳数值超出所在平台 C <code class="xref c c-func docutils literal notranslate"><span class="pre">localtime()</span></code> 函数的支持范围的话，并会在 <code class="xref c c-func docutils literal notranslate"><span class="pre">localtime()</span></code> 出错时引发 <a class="reference internal" href="exceptions.html#OSError" title="OSError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OSError</span></code></a> 而不是 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.fromordinal">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">date.</code><code class="sig-name descname">fromordinal</code><span class="sig-paren">(</span><em class="sig-param">ordinal</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.fromordinal" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回对应于预期格列高利历序号的日期，其中公元 1 年 1 月 1 日的序号为 1。</p>
|
||
<p>除非 <code class="docutils literal notranslate"><span class="pre">1</span> <span class="pre"><=</span> <span class="pre">ordinal</span> <span class="pre"><=</span> <span class="pre">date.max.toordinal()</span></code> 否则会引发 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。对于任意日期 <em>d</em>，<code class="docutils literal notranslate"><span class="pre">date.fromordinal(d.toordinal())</span> <span class="pre">==</span> <span class="pre">d</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.fromisoformat">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">date.</code><code class="sig-name descname">fromisoformat</code><span class="sig-paren">(</span><em class="sig-param">date_string</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.fromisoformat" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个对应于以 <code class="docutils literal notranslate"><span class="pre">YYYY-MM-DD</span></code> 格式给出的 <em>date_string</em> 的 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">date</span>
|
||
<span class="gp">>>> </span><span class="n">date</span><span class="o">.</span><span class="n">fromisoformat</span><span class="p">(</span><span class="s1">'2019-12-04'</span><span class="p">)</span>
|
||
<span class="go">datetime.date(2019, 12, 4)</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>这是 <a class="reference internal" href="#datetime.date.isoformat" title="datetime.date.isoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">date.isoformat()</span></code></a> 的逆操作。 它只支持 <code class="docutils literal notranslate"><span class="pre">YYYY-MM-DD</span></code> 格式。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.7 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.fromisocalendar">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">date.</code><code class="sig-name descname">fromisocalendar</code><span class="sig-paren">(</span><em class="sig-param">year</em>, <em class="sig-param">week</em>, <em class="sig-param">day</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.fromisocalendar" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回指定 year, week 和 day 所对应 ISO 历法日期的 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a>。 这是函数 <a class="reference internal" href="#datetime.date.isocalendar" title="datetime.date.isocalendar"><code class="xref py py-meth docutils literal notranslate"><span class="pre">date.isocalendar()</span></code></a> 的逆操作。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.8 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<p>类属性：</p>
|
||
<dl class="attribute">
|
||
<dt id="datetime.date.min">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">min</code><a class="headerlink" href="#datetime.date.min" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>最小的日期 <code class="docutils literal notranslate"><span class="pre">date(MINYEAR,</span> <span class="pre">1,</span> <span class="pre">1)</span></code> 。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.date.max">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">max</code><a class="headerlink" href="#datetime.date.max" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>最大的日期 ，<code class="docutils literal notranslate"><span class="pre">date(MAXYEAR,</span> <span class="pre">12,</span> <span class="pre">31)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.date.resolution">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">resolution</code><a class="headerlink" href="#datetime.date.resolution" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>两个日期对象的最小间隔，<code class="docutils literal notranslate"><span class="pre">timedelta(days=1)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<p>实例属性（只读）：</p>
|
||
<dl class="attribute">
|
||
<dt id="datetime.date.year">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">year</code><a class="headerlink" href="#datetime.date.year" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>在 <a class="reference internal" href="#datetime.MINYEAR" title="datetime.MINYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MINYEAR</span></code></a> 和 <a class="reference internal" href="#datetime.MAXYEAR" title="datetime.MAXYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MAXYEAR</span></code></a> 之间，包含边界。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.date.month">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">month</code><a class="headerlink" href="#datetime.date.month" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>1 至 12（含）</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.date.day">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">day</code><a class="headerlink" href="#datetime.date.day" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回1到指定年月的天数间的数字。</p>
|
||
</dd></dl>
|
||
|
||
<p>支持的运算：</p>
|
||
<table class="docutils align-default">
|
||
<colgroup>
|
||
<col style="width: 40%" />
|
||
<col style="width: 60%" />
|
||
</colgroup>
|
||
<thead>
|
||
<tr class="row-odd"><th class="head"><p>运算</p></th>
|
||
<th class="head"><p>结果：</p></th>
|
||
</tr>
|
||
</thead>
|
||
<tbody>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">date2</span> <span class="pre">=</span> <span class="pre">date1</span> <span class="pre">+</span> <span class="pre">timedelta</span></code></p></td>
|
||
<td><p><em>date2</em> 等于从 <em>date1</em> 减去 <code class="docutils literal notranslate"><span class="pre">timedelta.days</span></code> 天。 (1)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">date2</span> <span class="pre">=</span> <span class="pre">date1</span> <span class="pre">-</span> <span class="pre">timedelta</span></code></p></td>
|
||
<td><p>计算 <em>date2</em> 的值使得 <code class="docutils literal notranslate"><span class="pre">date2</span> <span class="pre">+</span> <span class="pre">timedelta</span> <span class="pre">==</span> <span class="pre">date1</span></code>。 (2)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">timedelta</span> <span class="pre">=</span> <span class="pre">date1</span> <span class="pre">-</span> <span class="pre">date2</span></code></p></td>
|
||
<td><p>(3)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">date1</span> <span class="pre"><</span> <span class="pre">date2</span></code></p></td>
|
||
<td><p>如果 <em>date1</em> 的时间在 <em>date2</em> 之前则认为 <em>date1</em> 小于 <em>date2</em> 。 (4)</p></td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
<p>注释：</p>
|
||
<ol class="arabic simple">
|
||
<li><p>如果 <code class="docutils literal notranslate"><span class="pre">timedelta.days</span> <span class="pre">></span> <span class="pre">0</span></code> 则 <em>date2</em> 将在时间线上前进，如果 <code class="docutils literal notranslate"><span class="pre">timedelta.days</span> <span class="pre"><</span> <span class="pre">0</span></code> 则将后退。 操作完成后 <code class="docutils literal notranslate"><span class="pre">date2</span> <span class="pre">-</span> <span class="pre">date1</span> <span class="pre">==</span> <span class="pre">timedelta.days</span></code>。 <code class="docutils literal notranslate"><span class="pre">timedelta.seconds</span></code> 和 <code class="docutils literal notranslate"><span class="pre">timedelta.microseconds</span></code> 会被忽略。 如果 <code class="docutils literal notranslate"><span class="pre">date2.year</span></code> 将小于 <a class="reference internal" href="#datetime.MINYEAR" title="datetime.MINYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MINYEAR</span></code></a> 或大于 <a class="reference internal" href="#datetime.MAXYEAR" title="datetime.MAXYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MAXYEAR</span></code></a> 则会引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a>。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">timedelta.seconds</span></code> 和 <code class="docutils literal notranslate"><span class="pre">timedelta.microseconds</span></code> 会被忽略。</p></li>
|
||
<li><p>此值完全精确且不会溢出。 操作完成后 timedelta.seconds 和 timedelta.microseconds 均为 0，并且 date2 + timedelta == date1。</p></li>
|
||
<li><p>换句话说，当且仅当 <code class="docutils literal notranslate"><span class="pre">date1.toordinal()</span> <span class="pre"><</span> <span class="pre">date2.toordinal()</span></code> 时 <code class="docutils literal notranslate"><span class="pre">date1</span> <span class="pre"><</span> <span class="pre">date2</span></code>。 日期比较会引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>，如果比较目标不为 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象的话。 不过也可能会返回 <code class="docutils literal notranslate"><span class="pre">NotImplemented</span></code>，如果比较目标具有 <code class="xref py py-meth docutils literal notranslate"><span class="pre">timetuple()</span></code> 属性的话。 这个钩子给予其他日期对象类型实现混合类型比较的机会。 否则，当 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象与不同类型的对象比较时将会引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>，除非是 <code class="docutils literal notranslate"><span class="pre">==</span></code> 或 <code class="docutils literal notranslate"><span class="pre">!=</span></code> 比较。 后两种情况将分别返回 <a class="reference internal" href="constants.html#False" title="False"><code class="xref py py-const docutils literal notranslate"><span class="pre">False</span></code></a> 或 <a class="reference internal" href="constants.html#True" title="True"><code class="xref py py-const docutils literal notranslate"><span class="pre">True</span></code></a>。</p></li>
|
||
</ol>
|
||
<p>在布尔运算中，所有 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象都会被视为真值。</p>
|
||
<p>实例方法：</p>
|
||
<dl class="method">
|
||
<dt id="datetime.date.replace">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">replace</code><span class="sig-paren">(</span><em class="sig-param">year=self.year</em>, <em class="sig-param">month=self.month</em>, <em class="sig-param">day=self.day</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.replace" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个具有同样值的日期，除非通过任何关键字参数给出了某些形参的新值。</p>
|
||
<p>示例:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">date</span>
|
||
<span class="gp">>>> </span><span class="n">d</span> <span class="o">=</span> <span class="n">date</span><span class="p">(</span><span class="mi">2002</span><span class="p">,</span> <span class="mi">12</span><span class="p">,</span> <span class="mi">31</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">d</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">day</span><span class="o">=</span><span class="mi">26</span><span class="p">)</span>
|
||
<span class="go">datetime.date(2002, 12, 26)</span>
|
||
</pre></div>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.timetuple">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">timetuple</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.timetuple" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个 <a class="reference internal" href="time.html#time.struct_time" title="time.struct_time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time.struct_time</span></code></a>，即 <a class="reference internal" href="time.html#time.localtime" title="time.localtime"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.localtime()</span></code></a> 所返回的类型。</p>
|
||
<p>hours, minutes 和 seconds 值均为 0，且 DST 旗标值为 -1。</p>
|
||
<p><code class="docutils literal notranslate"><span class="pre">d.timetuple()</span></code> 等价于:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">time</span><span class="o">.</span><span class="n">struct_time</span><span class="p">((</span><span class="n">d</span><span class="o">.</span><span class="n">year</span><span class="p">,</span> <span class="n">d</span><span class="o">.</span><span class="n">month</span><span class="p">,</span> <span class="n">d</span><span class="o">.</span><span class="n">day</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="n">d</span><span class="o">.</span><span class="n">weekday</span><span class="p">(),</span> <span class="n">yday</span><span class="p">,</span> <span class="o">-</span><span class="mi">1</span><span class="p">))</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>其中 <code class="docutils literal notranslate"><span class="pre">yday</span> <span class="pre">=</span> <span class="pre">d.toordinal()</span> <span class="pre">-</span> <span class="pre">date(d.year,</span> <span class="pre">1,</span> <span class="pre">1).toordinal()</span> <span class="pre">+</span> <span class="pre">1</span></code> 是当前年份中的日期序号，1 月 1 日的序号为 <code class="docutils literal notranslate"><span class="pre">1</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.toordinal">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">toordinal</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.toordinal" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回日期的预期格列高利历序号，其中公元 1 年 1 月 1 日的序号为 1。 对于任意 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象 <em>d</em>，<code class="docutils literal notranslate"><span class="pre">date.fromordinal(d.toordinal())</span> <span class="pre">==</span> <span class="pre">d</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.weekday">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">weekday</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.weekday" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个整数代表星期几，星期一为0，星期天为6。例如， <code class="docutils literal notranslate"><span class="pre">date(2002,</span> <span class="pre">12,</span> <span class="pre">4).weekday()</span> <span class="pre">==</span> <span class="pre">2</span></code>，表示的是星期三。参阅 <a class="reference internal" href="#datetime.date.isoweekday" title="datetime.date.isoweekday"><code class="xref py py-meth docutils literal notranslate"><span class="pre">isoweekday()</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.isoweekday">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">isoweekday</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.isoweekday" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个整数代表星期几，星期一为1，星期天为7。例如：<code class="docutils literal notranslate"><span class="pre">date(2002,</span> <span class="pre">12,</span> <span class="pre">4).isoweekday()</span> <span class="pre">==</span> <span class="pre">3</span></code>,表示星期三。参见 <a class="reference internal" href="#datetime.date.weekday" title="datetime.date.weekday"><code class="xref py py-meth docutils literal notranslate"><span class="pre">weekday()</span></code></a>, <a class="reference internal" href="#datetime.date.isocalendar" title="datetime.date.isocalendar"><code class="xref py py-meth docutils literal notranslate"><span class="pre">isocalendar()</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.isocalendar">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">isocalendar</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.isocalendar" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个三元元组，(ISO year, ISO week number, ISO weekday) 。</p>
|
||
<p>ISO 历法是一种被广泛使用的格列高利历。 <a class="footnote-reference brackets" href="#id7" id="id3">3</a></p>
|
||
<p>ISO 年由 52 或 53 个完整星期构成，每个星期开始于星期一结束于星期日。 一个 ISO 年的第一个星期就是（格列高利）历法的一年中第一个包含星期四的星期。 这被称为 1 号星期，这个星期四所在的 ISO 年与其所在的格列高利年相同。</p>
|
||
<p>例如，2004 年的第一天是星期四，因此 ISO 2004 年的第一个星期开始于 2003 年 12 月 29 日星期一，结束于 2004 年 1 月 4 日星期日:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">date</span>
|
||
<span class="gp">>>> </span><span class="n">date</span><span class="p">(</span><span class="mi">2003</span><span class="p">,</span> <span class="mi">12</span><span class="p">,</span> <span class="mi">29</span><span class="p">)</span><span class="o">.</span><span class="n">isocalendar</span><span class="p">()</span>
|
||
<span class="go">(2004, 1, 1)</span>
|
||
<span class="gp">>>> </span><span class="n">date</span><span class="p">(</span><span class="mi">2004</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">4</span><span class="p">)</span><span class="o">.</span><span class="n">isocalendar</span><span class="p">()</span>
|
||
<span class="go">(2004, 1, 7)</span>
|
||
</pre></div>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.isoformat">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">isoformat</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.isoformat" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个以 ISO 8601 格式 <code class="docutils literal notranslate"><span class="pre">YYYY-MM-DD</span></code> 来表示日期的字符串:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">date</span>
|
||
<span class="gp">>>> </span><span class="n">date</span><span class="p">(</span><span class="mi">2002</span><span class="p">,</span> <span class="mi">12</span><span class="p">,</span> <span class="mi">4</span><span class="p">)</span><span class="o">.</span><span class="n">isoformat</span><span class="p">()</span>
|
||
<span class="go">'2002-12-04'</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>这是 <a class="reference internal" href="#datetime.date.fromisoformat" title="datetime.date.fromisoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">date.fromisoformat()</span></code></a> 的逆操作。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.__str__">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">__str__</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.__str__" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>对于日期对象 <em>d</em>, <code class="docutils literal notranslate"><span class="pre">str(d)</span></code> 等价于 <code class="docutils literal notranslate"><span class="pre">d.isoformat()</span></code> 。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.ctime">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">ctime</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.ctime" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个表示日期的字符串:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">date</span>
|
||
<span class="gp">>>> </span><span class="n">date</span><span class="p">(</span><span class="mi">2002</span><span class="p">,</span> <span class="mi">12</span><span class="p">,</span> <span class="mi">4</span><span class="p">)</span><span class="o">.</span><span class="n">ctime</span><span class="p">()</span>
|
||
<span class="go">'Wed Dec 4 00:00:00 2002'</span>
|
||
</pre></div>
|
||
</div>
|
||
<p><code class="docutils literal notranslate"><span class="pre">d.ctime()</span></code> 等效于:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">time</span><span class="o">.</span><span class="n">ctime</span><span class="p">(</span><span class="n">time</span><span class="o">.</span><span class="n">mktime</span><span class="p">(</span><span class="n">d</span><span class="o">.</span><span class="n">timetuple</span><span class="p">()))</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>在原生 C <code class="xref c c-func docutils literal notranslate"><span class="pre">ctime()</span></code> 函数遵循 C 标准的平台上 (<a class="reference internal" href="time.html#time.ctime" title="time.ctime"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.ctime()</span></code></a> 会发起对该函数的调用，但 <a class="reference internal" href="#datetime.date.ctime" title="datetime.date.ctime"><code class="xref py py-meth docutils literal notranslate"><span class="pre">date.ctime()</span></code></a> 并不会) 。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.strftime">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">strftime</code><span class="sig-paren">(</span><em class="sig-param">format</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.strftime" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个由显式格式字符串所指明的代表日期的字符串。 表示时、分或秒的格式代码值将为 0。 要获取格式指令的完整列表请参阅 <a class="reference internal" href="#strftime-strptime-behavior"><span class="std std-ref">strftime() 和 strptime() 的行为</span></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.date.__format__">
|
||
<code class="sig-prename descclassname">date.</code><code class="sig-name descname">__format__</code><span class="sig-paren">(</span><em class="sig-param">format</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.date.__format__" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>与 <a class="reference internal" href="#datetime.date.strftime" title="datetime.date.strftime"><code class="xref py py-meth docutils literal notranslate"><span class="pre">date.strftime()</span></code></a> 相同。 此方法使得为 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象指定以 <a class="reference internal" href="../reference/lexical_analysis.html#f-strings"><span class="std std-ref">格式化字符串字面值</span></a> 表示的格式化字符串以及使用 <a class="reference internal" href="stdtypes.html#str.format" title="str.format"><code class="xref py py-meth docutils literal notranslate"><span class="pre">str.format()</span></code></a> 进行格式化成为可能。 要获取格式指令的完整列表，请参阅 <a class="reference internal" href="#strftime-strptime-behavior"><span class="std std-ref">strftime() 和 strptime() 的行为</span></a>。</p>
|
||
</dd></dl>
|
||
|
||
<section id="examples-of-usage-date">
|
||
<h3><a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 用法示例<a class="headerlink" href="#examples-of-usage-date" title="永久链接至标题">¶</a></h3>
|
||
<p>计算距离特定事件天数的例子:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">import</span> <span class="nn">time</span>
|
||
<span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">date</span>
|
||
<span class="gp">>>> </span><span class="n">today</span> <span class="o">=</span> <span class="n">date</span><span class="o">.</span><span class="n">today</span><span class="p">()</span>
|
||
<span class="gp">>>> </span><span class="n">today</span>
|
||
<span class="go">datetime.date(2007, 12, 5)</span>
|
||
<span class="gp">>>> </span><span class="n">today</span> <span class="o">==</span> <span class="n">date</span><span class="o">.</span><span class="n">fromtimestamp</span><span class="p">(</span><span class="n">time</span><span class="o">.</span><span class="n">time</span><span class="p">())</span>
|
||
<span class="go">True</span>
|
||
<span class="gp">>>> </span><span class="n">my_birthday</span> <span class="o">=</span> <span class="n">date</span><span class="p">(</span><span class="n">today</span><span class="o">.</span><span class="n">year</span><span class="p">,</span> <span class="mi">6</span><span class="p">,</span> <span class="mi">24</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="k">if</span> <span class="n">my_birthday</span> <span class="o"><</span> <span class="n">today</span><span class="p">:</span>
|
||
<span class="gp">... </span> <span class="n">my_birthday</span> <span class="o">=</span> <span class="n">my_birthday</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">year</span><span class="o">=</span><span class="n">today</span><span class="o">.</span><span class="n">year</span> <span class="o">+</span> <span class="mi">1</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">my_birthday</span>
|
||
<span class="go">datetime.date(2008, 6, 24)</span>
|
||
<span class="gp">>>> </span><span class="n">time_to_birthday</span> <span class="o">=</span> <span class="nb">abs</span><span class="p">(</span><span class="n">my_birthday</span> <span class="o">-</span> <span class="n">today</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">time_to_birthday</span><span class="o">.</span><span class="n">days</span>
|
||
<span class="go">202</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>使用 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 的更多例子：</p>
|
||
<div class="highlight-pycon3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">date</span>
|
||
<span class="gp">>>> </span><span class="n">d</span> <span class="o">=</span> <span class="n">date</span><span class="o">.</span><span class="n">fromordinal</span><span class="p">(</span><span class="mi">730920</span><span class="p">)</span> <span class="c1"># 730920th day after 1. 1. 0001</span>
|
||
<span class="gp">>>> </span><span class="n">d</span>
|
||
<span class="go">datetime.date(2002, 3, 11)</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Methods related to formatting string output</span>
|
||
<span class="gp">>>> </span><span class="n">d</span><span class="o">.</span><span class="n">isoformat</span><span class="p">()</span>
|
||
<span class="go">'2002-03-11'</span>
|
||
<span class="gp">>>> </span><span class="n">d</span><span class="o">.</span><span class="n">strftime</span><span class="p">(</span><span class="s2">"</span><span class="si">%d</span><span class="s2">/%m/%y"</span><span class="p">)</span>
|
||
<span class="go">'11/03/02'</span>
|
||
<span class="gp">>>> </span><span class="n">d</span><span class="o">.</span><span class="n">strftime</span><span class="p">(</span><span class="s2">"%A </span><span class="si">%d</span><span class="s2">. %B %Y"</span><span class="p">)</span>
|
||
<span class="go">'Monday 11. March 2002'</span>
|
||
<span class="gp">>>> </span><span class="n">d</span><span class="o">.</span><span class="n">ctime</span><span class="p">()</span>
|
||
<span class="go">'Mon Mar 11 00:00:00 2002'</span>
|
||
<span class="gp">>>> </span><span class="s1">'The </span><span class="si">{1}</span><span class="s1"> is {0:</span><span class="si">%d</span><span class="s1">}, the </span><span class="si">{2}</span><span class="s1"> is {0:%B}.'</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">d</span><span class="p">,</span> <span class="s2">"day"</span><span class="p">,</span> <span class="s2">"month"</span><span class="p">)</span>
|
||
<span class="go">'The day is 11, the month is March.'</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Methods for to extracting 'components' under different calendars</span>
|
||
<span class="gp">>>> </span><span class="n">t</span> <span class="o">=</span> <span class="n">d</span><span class="o">.</span><span class="n">timetuple</span><span class="p">()</span>
|
||
<span class="gp">>>> </span><span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="n">t</span><span class="p">:</span>
|
||
<span class="gp">... </span> <span class="nb">print</span><span class="p">(</span><span class="n">i</span><span class="p">)</span>
|
||
<span class="go">2002 # year</span>
|
||
<span class="go">3 # month</span>
|
||
<span class="go">11 # day</span>
|
||
<span class="go">0</span>
|
||
<span class="go">0</span>
|
||
<span class="go">0</span>
|
||
<span class="go">0 # weekday (0 = Monday)</span>
|
||
<span class="go">70 # 70th day in the year</span>
|
||
<span class="go">-1</span>
|
||
<span class="gp">>>> </span><span class="n">ic</span> <span class="o">=</span> <span class="n">d</span><span class="o">.</span><span class="n">isocalendar</span><span class="p">()</span>
|
||
<span class="gp">>>> </span><span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="n">ic</span><span class="p">:</span>
|
||
<span class="gp">... </span> <span class="nb">print</span><span class="p">(</span><span class="n">i</span><span class="p">)</span>
|
||
<span class="go">2002 # ISO year</span>
|
||
<span class="go">11 # ISO week number</span>
|
||
<span class="go">1 # ISO day number ( 1 = Monday )</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># A date object is immutable; all operations produce a new object</span>
|
||
<span class="gp">>>> </span><span class="n">d</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">year</span><span class="o">=</span><span class="mi">2005</span><span class="p">)</span>
|
||
<span class="go">datetime.date(2005, 3, 11)</span>
|
||
</pre></div>
|
||
</div>
|
||
</section>
|
||
</section>
|
||
<section id="datetime-objects">
|
||
<span id="datetime-datetime"></span><h2><a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象<a class="headerlink" href="#datetime-objects" title="永久链接至标题">¶</a></h2>
|
||
<p><a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象是包含来自 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象和 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象的所有信息的单一对象。</p>
|
||
<p>与 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象一样，<a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 假定当前的格列高利历向前后两个方向无限延伸；与 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象一样，<a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 假定每一天恰好有 3600*24 秒。</p>
|
||
<p>构造器 ：</p>
|
||
<dl class="class">
|
||
<dt id="datetime.datetime">
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">datetime</code><span class="sig-paren">(</span><em class="sig-param">year</em>, <em class="sig-param">month</em>, <em class="sig-param">day</em>, <em class="sig-param">hour=0</em>, <em class="sig-param">minute=0</em>, <em class="sig-param">second=0</em>, <em class="sig-param">microsecond=0</em>, <em class="sig-param">tzinfo=None</em>, <em class="sig-param">*</em>, <em class="sig-param">fold=0</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime" title="永久链接至目标">¶</a></dt>
|
||
<dd><p><em>year</em>, <em>month</em> 和 <em>day</em> 参数是必须的。 <em>tzinfo</em> 可以是 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或者是一个 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类的实例。 其余的参数必须是在下面范围内的整数：</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">MINYEAR</span> <span class="pre"><=</span> <span class="pre">year</span> <span class="pre"><=</span> <span class="pre">MAXYEAR</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">1</span> <span class="pre"><=</span> <span class="pre">month</span> <span class="pre"><=</span> <span class="pre">12</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">1</span> <span class="pre"><=</span> <span class="pre">day</span> <span class="pre"><=</span> <span class="pre">指定年月的天数</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">hour</span> <span class="pre"><</span> <span class="pre">24</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">minute</span> <span class="pre"><</span> <span class="pre">60</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">second</span> <span class="pre"><</span> <span class="pre">60</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">microsecond</span> <span class="pre"><</span> <span class="pre">1000000</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">fold</span> <span class="pre">in</span> <span class="pre">[0,</span> <span class="pre">1]</span></code>.</p></li>
|
||
</ul>
|
||
<p>如果参数不在这些范围内，则抛出 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a> 异常。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.6 新版功能: </span>增加了 <code class="docutils literal notranslate"><span class="pre">fold</span></code> 参数。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<p>其它构造器，所有的类方法：</p>
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.today">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">today</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.today" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回表示当前地方时的 datetime 对象，其中 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
|
||
<p>等价于:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">datetime</span><span class="o">.</span><span class="n">fromtimestamp</span><span class="p">(</span><span class="n">time</span><span class="o">.</span><span class="n">time</span><span class="p">())</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>另请参阅 <a class="reference internal" href="#datetime.datetime.now" title="datetime.datetime.now"><code class="xref py py-meth docutils literal notranslate"><span class="pre">now()</span></code></a>, <a class="reference internal" href="#datetime.datetime.fromtimestamp" title="datetime.datetime.fromtimestamp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromtimestamp()</span></code></a>。</p>
|
||
<p>此方法的功能等价于 <a class="reference internal" href="#datetime.datetime.now" title="datetime.datetime.now"><code class="xref py py-meth docutils literal notranslate"><span class="pre">now()</span></code></a>，但是不带 <code class="docutils literal notranslate"><span class="pre">tz</span></code> 形参。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.now">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">now</code><span class="sig-paren">(</span><em class="sig-param">tz=None</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.now" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回表示当前地方时的 date 和 time 对象。</p>
|
||
<p>如果可选参数 <em>tz</em> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或未指定，这就类似于 <a class="reference internal" href="#datetime.datetime.today" title="datetime.datetime.today"><code class="xref py py-meth docutils literal notranslate"><span class="pre">today()</span></code></a>，但该方法会在可能的情况下提供比通过 <a class="reference internal" href="time.html#time.time" title="time.time"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.time()</span></code></a> 时间戳所获时间值更高的精度（例如，在提供了 C <code class="xref c c-func docutils literal notranslate"><span class="pre">gettimeofday()</span></code> 函数的平台上就可以做到这一点）。</p>
|
||
<p>如果 <em>tz</em> 不为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，它必须是 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类的一个实例，并且当前日期和时间将被转换到 <em>tz</em> 时区。</p>
|
||
<p>此函数可以替代 <a class="reference internal" href="#datetime.datetime.today" title="datetime.datetime.today"><code class="xref py py-meth docutils literal notranslate"><span class="pre">today()</span></code></a> 和 <a class="reference internal" href="#datetime.datetime.utcnow" title="datetime.datetime.utcnow"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcnow()</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.utcnow">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">utcnow</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.utcnow" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回表示当前 UTC 时间的 date 和 time，其中 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
|
||
<p>这类似于 <a class="reference internal" href="#datetime.datetime.now" title="datetime.datetime.now"><code class="xref py py-meth docutils literal notranslate"><span class="pre">now()</span></code></a>，但返回的是当前 UTC 日期和时间，类型为简单型 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象。 感知型的当前 UTC 日期时间可通过调用 <code class="docutils literal notranslate"><span class="pre">datetime.now(timezone.utc)</span></code> 来获得。 另请参阅 <a class="reference internal" href="#datetime.datetime.now" title="datetime.datetime.now"><code class="xref py py-meth docutils literal notranslate"><span class="pre">now()</span></code></a>。</p>
|
||
<div class="admonition warning">
|
||
<p class="admonition-title">警告</p>
|
||
<p>由于简单型 <code class="docutils literal notranslate"><span class="pre">datetime</span></code> 对象会被许多 <code class="docutils literal notranslate"><span class="pre">datetime</span></code> 方法当作本地时间来处理，最好是使用感知型日期时间对象来表示 UTC 时间。 因此，创建表示当前 UTC 时间的对象的推荐方式是通过调用 <code class="docutils literal notranslate"><span class="pre">datetime.now(timezone.utc)</span></code>。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.fromtimestamp">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">fromtimestamp</code><span class="sig-paren">(</span><em class="sig-param">timestamp</em>, <em class="sig-param">tz=None</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.fromtimestamp" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回 POSIX 时间戳对应的本地日期和时间，如 <a class="reference internal" href="time.html#time.time" title="time.time"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.time()</span></code></a> 返回的。 如果可选参数 <em>tz</em> 指定为 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或未指定，时间戳将转换为平台的本地日期和时间，并且返回的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象将为简单型。</p>
|
||
<p>如果 <em>tz</em> 不为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，它必须是 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类的一个实例，并且时间戳将被转换到 <em>tz</em> 指定的时区。</p>
|
||
<p><a class="reference internal" href="#datetime.datetime.fromtimestamp" title="datetime.datetime.fromtimestamp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromtimestamp()</span></code></a> 可能会引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a>，如果时间戳数值超出所在平台 C <code class="xref c c-func docutils literal notranslate"><span class="pre">localtime()</span></code> 或 <code class="xref c c-func docutils literal notranslate"><span class="pre">gmtime()</span></code> 函数的支持范围的话，并会在 <code class="xref c c-func docutils literal notranslate"><span class="pre">localtime()</span></code> 或 <code class="xref c c-func docutils literal notranslate"><span class="pre">gmtime()</span></code> 报错时引发 <a class="reference internal" href="exceptions.html#OSError" title="OSError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OSError</span></code></a>。 通常该数值会被限制在 1970 年至 2038 年之间。 请注意在时间戳概念包含闰秒的非 POSIX 系统上，闰秒会被 <a class="reference internal" href="#datetime.datetime.fromtimestamp" title="datetime.datetime.fromtimestamp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromtimestamp()</span></code></a> 所忽略，结果可能导致两个相差一秒的时间戳产生相同的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象。 相比 <a class="reference internal" href="#datetime.datetime.utcfromtimestamp" title="datetime.datetime.utcfromtimestamp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcfromtimestamp()</span></code></a> 更推荐使用此方法。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.3 版更改: </span>引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a> 而不是 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>，如果时间戳数值超出所在平台 C <code class="xref c c-func docutils literal notranslate"><span class="pre">localtime()</span></code> 或 <code class="xref c c-func docutils literal notranslate"><span class="pre">gmtime()</span></code> 函数的支持范围的话。 并会在 <code class="xref c c-func docutils literal notranslate"><span class="pre">localtime()</span></code> 或 <code class="xref c c-func docutils literal notranslate"><span class="pre">gmtime()</span></code> 出错时引发 <a class="reference internal" href="exceptions.html#OSError" title="OSError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OSError</span></code></a> 而不是 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。</p>
|
||
</div>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.6 版更改: </span><a class="reference internal" href="#datetime.datetime.fromtimestamp" title="datetime.datetime.fromtimestamp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromtimestamp()</span></code></a> 可能返回 <a class="reference internal" href="#datetime.datetime.fold" title="datetime.datetime.fold"><code class="xref py py-attr docutils literal notranslate"><span class="pre">fold</span></code></a> 值设为 1 的实例。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.utcfromtimestamp">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">utcfromtimestamp</code><span class="sig-paren">(</span><em class="sig-param">timestamp</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.utcfromtimestamp" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回对应于 POSIX 时间戳的 UTC <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a>，其中 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 值为 <code class="docutils literal notranslate"><span class="pre">None</span></code>。 （结果为简单型对象。）</p>
|
||
<p>这可能引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a>，如果时间戳数值超出所在平台 C <code class="xref c c-func docutils literal notranslate"><span class="pre">gmtime()</span></code> 函数的支持范围的话，并会在 <code class="xref c c-func docutils literal notranslate"><span class="pre">gmtime()</span></code> 报错时引发 <a class="reference internal" href="exceptions.html#OSError" title="OSError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OSError</span></code></a>。 通常该数值会被限制在 1970 至 2038 年之间。</p>
|
||
<p>要得到一个感知型 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象，应调用 <a class="reference internal" href="#datetime.datetime.fromtimestamp" title="datetime.datetime.fromtimestamp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromtimestamp()</span></code></a>:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">datetime</span><span class="o">.</span><span class="n">fromtimestamp</span><span class="p">(</span><span class="n">timestamp</span><span class="p">,</span> <span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>在 POSIX 兼容的平台上，它等价于以下表达式:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">datetime</span><span class="p">(</span><span class="mi">1970</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span> <span class="o">+</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">seconds</span><span class="o">=</span><span class="n">timestamp</span><span class="p">)</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>不同之处在于后一种形式总是支持完整年份范围：从 <a class="reference internal" href="#datetime.MINYEAR" title="datetime.MINYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MINYEAR</span></code></a> 到 <a class="reference internal" href="#datetime.MAXYEAR" title="datetime.MAXYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MAXYEAR</span></code></a> 的开区间。</p>
|
||
<div class="admonition warning">
|
||
<p class="admonition-title">警告</p>
|
||
<p>由于简单型 <code class="docutils literal notranslate"><span class="pre">datetime</span></code> 对象会被许多 <code class="docutils literal notranslate"><span class="pre">datetime</span></code> 方法当作本地时间来处理，最好是使用感知型日期时间对象来表示 UTC 时间。 因此，创建表示特定 UTC 时间戳的日期时间对象的推荐方式是通过调用 <code class="docutils literal notranslate"><span class="pre">datetime.fromtimestamp(timestamp,</span> <span class="pre">tz=timezone.utc)</span></code>。</p>
|
||
</div>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.3 版更改: </span>引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a> 而不是 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>，如果时间戳数值超出所在平台 C <code class="xref c c-func docutils literal notranslate"><span class="pre">gmtime()</span></code> 函数的支持范围的话。 并会在 <code class="xref c c-func docutils literal notranslate"><span class="pre">gmtime()</span></code> 出错时引发 <a class="reference internal" href="exceptions.html#OSError" title="OSError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OSError</span></code></a> 而不是 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.fromordinal">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">fromordinal</code><span class="sig-paren">(</span><em class="sig-param">ordinal</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.fromordinal" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回对应于预期格列高利历序号的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a>，其中公元 1 年 1 月 1 日的序号为 1。 除非 <code class="docutils literal notranslate"><span class="pre">1</span> <span class="pre"><=</span> <span class="pre">ordinal</span> <span class="pre"><=</span> <span class="pre">datetime.max.toordinal()</span></code> 否则会引发 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。 结果的 hour, minute, second 和 microsecond 值均为 0，并且 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 值为 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.combine">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">combine</code><span class="sig-paren">(</span><em class="sig-param">date</em>, <em class="sig-param">time</em>, <em class="sig-param">tzinfo=self.tzinfo</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.combine" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个新的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象，对象的日期部分等于给定的 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象的值，而其时间部分等于给定的 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象的值。 如果提供了 <em>tzinfo</em> 参数，其值会被用来设置结果的 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性，否则将使用 <em>time</em> 参数的 <a class="reference internal" href="#datetime.time.tzinfo" title="datetime.time.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性。</p>
|
||
<p>对于任意 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象 <em>d</em>，<code class="docutils literal notranslate"><span class="pre">d</span> <span class="pre">==</span> <span class="pre">datetime.combine(d.date(),</span> <span class="pre">d.time(),</span> <span class="pre">d.tzinfo)</span></code>。 如果 date 是一个 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象，它的时间部分和 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性会被忽略。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.6 版更改: </span>增加了 <em>tzinfo</em> 参数。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.fromisoformat">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">fromisoformat</code><span class="sig-paren">(</span><em class="sig-param">date_string</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.fromisoformat" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个对应于 <a class="reference internal" href="#datetime.date.isoformat" title="datetime.date.isoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">date.isoformat()</span></code></a> 和 <a class="reference internal" href="#datetime.datetime.isoformat" title="datetime.datetime.isoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.isoformat()</span></code></a> 所提供的某一种 <em>date_string</em> 的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象。</p>
|
||
<p>特别地，此函数支持以下格式的字符串：</p>
|
||
<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>YYYY-MM-DD[*HH[:MM[:SS[.fff[fff]]]][+HH:MM[:SS[.ffffff]]]]
|
||
</pre></div>
|
||
</div>
|
||
<p>其中 <code class="docutils literal notranslate"><span class="pre">*</span></code> 可以匹配任意的单个字符。</p>
|
||
<div class="admonition caution">
|
||
<p class="admonition-title">警告</p>
|
||
<p>此函数 <em>并不</em> 支持解析任意 ISO 8601 字符串 —— 它的目的只是作为 <a class="reference internal" href="#datetime.datetime.isoformat" title="datetime.datetime.isoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.isoformat()</span></code></a> 的逆操作。 在第三方包 <a class="reference external" href="https://dateutil.readthedocs.io/en/stable/parser.html#dateutil.parser.isoparse">dateutil</a> 中提供了一个更完善的 ISO 8601 解析器 <code class="docutils literal notranslate"><span class="pre">dateutil.parser.isoparse</span></code>。</p>
|
||
</div>
|
||
<p>示例:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">datetime</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="o">.</span><span class="n">fromisoformat</span><span class="p">(</span><span class="s1">'2011-11-04'</span><span class="p">)</span>
|
||
<span class="go">datetime.datetime(2011, 11, 4, 0, 0)</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="o">.</span><span class="n">fromisoformat</span><span class="p">(</span><span class="s1">'2011-11-04T00:05:23'</span><span class="p">)</span>
|
||
<span class="go">datetime.datetime(2011, 11, 4, 0, 5, 23)</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="o">.</span><span class="n">fromisoformat</span><span class="p">(</span><span class="s1">'2011-11-04 00:05:23.283'</span><span class="p">)</span>
|
||
<span class="go">datetime.datetime(2011, 11, 4, 0, 5, 23, 283000)</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="o">.</span><span class="n">fromisoformat</span><span class="p">(</span><span class="s1">'2011-11-04 00:05:23.283+00:00'</span><span class="p">)</span>
|
||
<span class="go">datetime.datetime(2011, 11, 4, 0, 5, 23, 283000, tzinfo=datetime.timezone.utc)</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="o">.</span><span class="n">fromisoformat</span><span class="p">(</span><span class="s1">'2011-11-04T00:05:23+04:00'</span><span class="p">)</span>
|
||
<span class="go">datetime.datetime(2011, 11, 4, 0, 5, 23,</span>
|
||
<span class="go"> tzinfo=datetime.timezone(datetime.timedelta(seconds=14400)))</span>
|
||
</pre></div>
|
||
</div>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.7 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.fromisocalendar">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">fromisocalendar</code><span class="sig-paren">(</span><em class="sig-param">year</em>, <em class="sig-param">week</em>, <em class="sig-param">day</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.fromisocalendar" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回以 year, week 和 day 值指明的 ISO 历法日期所对应的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a>。 该datetime 对象的非日期部分将使用其标准默认值来填充。 这是函数 <a class="reference internal" href="#datetime.datetime.isocalendar" title="datetime.datetime.isocalendar"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.isocalendar()</span></code></a> 的逆操作。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.8 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.strptime">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">strptime</code><span class="sig-paren">(</span><em class="sig-param">date_string</em>, <em class="sig-param">format</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.strptime" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个对应于 <em>date_string</em>，根据 <em>format</em> 进行解析得到的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象。</p>
|
||
<p>这相当于：</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">datetime</span><span class="p">(</span><span class="o">*</span><span class="p">(</span><span class="n">time</span><span class="o">.</span><span class="n">strptime</span><span class="p">(</span><span class="n">date_string</span><span class="p">,</span> <span class="nb">format</span><span class="p">)[</span><span class="mi">0</span><span class="p">:</span><span class="mi">6</span><span class="p">]))</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>如果 date_string 和 format 无法被 <a class="reference internal" href="time.html#time.strptime" title="time.strptime"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.strptime()</span></code></a> 解析或它返回一个不是时间元组的值，则将引发 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。 要获取格式化指令的完整列表，请参阅 <a class="reference internal" href="#strftime-strptime-behavior"><span class="std std-ref">strftime() 和 strptime() 的行为</span></a>。</p>
|
||
</dd></dl>
|
||
|
||
<p>类属性：</p>
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.min">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">min</code><a class="headerlink" href="#datetime.datetime.min" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>最早的可表示 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a>，<code class="docutils literal notranslate"><span class="pre">datetime(MINYEAR,</span> <span class="pre">1,</span> <span class="pre">1,</span> <span class="pre">tzinfo=None)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.max">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">max</code><a class="headerlink" href="#datetime.datetime.max" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>最晚的可表示 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a>，<code class="docutils literal notranslate"><span class="pre">datetime(MAXYEAR,</span> <span class="pre">12,</span> <span class="pre">31,</span> <span class="pre">23,</span> <span class="pre">59,</span> <span class="pre">59,</span> <span class="pre">999999,</span> <span class="pre">tzinfo=None)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.resolution">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">resolution</code><a class="headerlink" href="#datetime.datetime.resolution" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>两个不相等的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象之间可能的最小间隔，<code class="docutils literal notranslate"><span class="pre">timedelta(microseconds=1)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<p>实例属性（只读）：</p>
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.year">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">year</code><a class="headerlink" href="#datetime.datetime.year" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>在 <a class="reference internal" href="#datetime.MINYEAR" title="datetime.MINYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MINYEAR</span></code></a> 和 <a class="reference internal" href="#datetime.MAXYEAR" title="datetime.MAXYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MAXYEAR</span></code></a> 之间，包含边界。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.month">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">month</code><a class="headerlink" href="#datetime.datetime.month" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>1 至 12（含）</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.day">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">day</code><a class="headerlink" href="#datetime.datetime.day" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回1到指定年月的天数间的数字。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.hour">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">hour</code><a class="headerlink" href="#datetime.datetime.hour" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">range(24)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.minute">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">minute</code><a class="headerlink" href="#datetime.datetime.minute" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">range(60)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.second">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">second</code><a class="headerlink" href="#datetime.datetime.second" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">range(60)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.microsecond">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">microsecond</code><a class="headerlink" href="#datetime.datetime.microsecond" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">range(1000000)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.tzinfo">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">tzinfo</code><a class="headerlink" href="#datetime.datetime.tzinfo" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>作为 <em>tzinfo</em> 参数被传给 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 构造器的对象，如果没有传入值则为 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.datetime.fold">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">fold</code><a class="headerlink" href="#datetime.datetime.fold" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">[0,</span> <span class="pre">1]</span></code>。 用于在重复的时间段中消除边界时间歧义。 （当夏令时结束时回拨时钟或由于政治原因导致当明时区的 UTC 时差减少就会出现重复的时间段。） 取值 0 (1) 表示两个时刻早于（晚于）所代表的同一边界时间。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.6 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<p>支持的运算：</p>
|
||
<table class="docutils align-default">
|
||
<colgroup>
|
||
<col style="width: 55%" />
|
||
<col style="width: 45%" />
|
||
</colgroup>
|
||
<thead>
|
||
<tr class="row-odd"><th class="head"><p>运算</p></th>
|
||
<th class="head"><p>结果：</p></th>
|
||
</tr>
|
||
</thead>
|
||
<tbody>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">datetime2</span> <span class="pre">=</span> <span class="pre">datetime1</span> <span class="pre">+</span> <span class="pre">timedelta</span></code></p></td>
|
||
<td><p>(1)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">datetime2</span> <span class="pre">=</span> <span class="pre">datetime1</span> <span class="pre">-</span> <span class="pre">timedelta</span></code></p></td>
|
||
<td><p>(2)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">timedelta</span> <span class="pre">=</span> <span class="pre">datetime1</span> <span class="pre">-</span> <span class="pre">datetime2</span></code></p></td>
|
||
<td><p>(3)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">datetime1</span> <span class="pre"><</span> <span class="pre">datetime2</span></code></p></td>
|
||
<td><p>比较 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 与 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a>。 (4)</p></td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
<ol class="arabic">
|
||
<li><p>datetime2 是从 datetime1 去掉了一段 timedelta 的结果，如果 <code class="docutils literal notranslate"><span class="pre">timedelta.days</span></code> > 0 则是在时间线上前进，如果 <code class="docutils literal notranslate"><span class="pre">timedelta.days</span></code> < 0 则是在时间线上后退。 该结果具有与输入的 datetime 相同的 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性，并且操作完成后 datetime2 - datetime1 == timedelta。 如果 datetime2.year 将要小于 <a class="reference internal" href="#datetime.MINYEAR" title="datetime.MINYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MINYEAR</span></code></a> 或大于 <a class="reference internal" href="#datetime.MAXYEAR" title="datetime.MAXYEAR"><code class="xref py py-const docutils literal notranslate"><span class="pre">MAXYEAR</span></code></a> 则会引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a>。 请注意即使输入的是一个感知型对象，该方法也不会进行时区调整。</p></li>
|
||
<li><p>计算 datetime2 使得 datetime2 + timedelta == datetime1。 与相加操作一样，结果具有与输入的 datetime 相同的 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性，即使输入的是一个感知型对象，该方法也不会进行时区调整。</p></li>
|
||
<li><p>从一个 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 减去一个 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 仅对两个操作数均为简单型或均为感知型时有定义。 如果一个是感知型而另一个是简单型，则会引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>。</p>
|
||
<p>如果两个操作数都是简单型，或都是感知型并且具有相同的 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性，则 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性会被忽略，并且结果会是一个使得 <code class="docutils literal notranslate"><span class="pre">datetime2</span> <span class="pre">+</span> <span class="pre">t</span> <span class="pre">==</span> <span class="pre">datetime1</span></code> 的 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象 <em>t</em>。 在此情况下不会进行时区调整。</p>
|
||
<p>如果两个操作数都是感知型且具有不同的 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性，<code class="docutils literal notranslate"><span class="pre">a-b</span></code> 操作的效果就如同 <em>a</em> 和 <em>b</em> 首先被转换为简单型 UTC 日期时间。 结果将是 <code class="docutils literal notranslate"><span class="pre">(a.replace(tzinfo=None)</span> <span class="pre">-</span> <span class="pre">a.utcoffset())</span> <span class="pre">-</span> <span class="pre">(b.replace(tzinfo=None)</span> <span class="pre">-</span> <span class="pre">b.utcoffset())</span></code>，除非具体实现绝对不溢出。</p>
|
||
</li>
|
||
<li><p>当 <em>datetime1</em> 的时间在 <em>datetime2</em> 之前则认为 <em>datetime1</em> 小于 <em>datetime2</em>。</p>
|
||
<p>如果比较的一方是简单型而另一方是感知型，则如果尝试进行顺序比较将引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>。 对于相等比较，简单型实例将永远不等于感知型实例。</p>
|
||
<p>如果两个比较方都是感知型，且具有相同的 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性，则相同的 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性会被忽略并对基本日期时间值进行比较。 如果两个比较方都是感知型且具有不同的 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性，则两个比较方将首先通过减去它们的 UTC 差值（使用 <code class="docutils literal notranslate"><span class="pre">self.utcoffset()</span></code> 获取）来进行调整。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.3 版更改: </span>感知型和简单型 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 实例之间的相等比较不会引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>。</p>
|
||
</div>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">注解</p>
|
||
<p>为了防止比较操作回退为默认的对象地址比较方式，datetime 比较通常会引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>，如果比较目标不同样为 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象的话。 不过也可能会返回 <code class="docutils literal notranslate"><span class="pre">NotImplemented</span></code>，如果比较目标具有 <code class="xref py py-meth docutils literal notranslate"><span class="pre">timetuple()</span></code> 属性的话。 这个钩子给予其他种类的日期对象实现混合类型比较的机会。 如果未实现，则当 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象与不同类型比较时将会引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>，除非是 <code class="docutils literal notranslate"><span class="pre">==</span></code> 或 <code class="docutils literal notranslate"><span class="pre">!=</span></code> 比较。 后两种情况将分别返回 <a class="reference internal" href="constants.html#False" title="False"><code class="xref py py-const docutils literal notranslate"><span class="pre">False</span></code></a> 或 <a class="reference internal" href="constants.html#True" title="True"><code class="xref py py-const docutils literal notranslate"><span class="pre">True</span></code></a>。</p>
|
||
</div>
|
||
</li>
|
||
</ol>
|
||
<p>实例方法：</p>
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.date">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">date</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.date" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回具有同样 year, month 和 day 值的 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.time">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">time</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.time" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回具有同样 hour, minute, second, microsecond 和 fold 值的 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象。 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 值为 <code class="docutils literal notranslate"><span class="pre">None</span></code>。 另请参见 <a class="reference internal" href="#datetime.datetime.timetz" title="datetime.datetime.timetz"><code class="xref py py-meth docutils literal notranslate"><span class="pre">timetz()</span></code></a> 方法。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.6 版更改: </span>fold 值会被复制给返回的 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.timetz">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">timetz</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.timetz" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回具有同样 hour, minute, second, microsecond, fold 和 tzinfo 属性性的 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象。 另请参见 <a class="reference internal" href="time.html#module-time" title="time: Time access and conversions."><code class="xref py py-meth docutils literal notranslate"><span class="pre">time()</span></code></a> 方法。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.6 版更改: </span>fold 值会被复制给返回的 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.replace">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">replace</code><span class="sig-paren">(</span><em class="sig-param">year=self.year</em>, <em class="sig-param">month=self.month</em>, <em class="sig-param">day=self.day</em>, <em class="sig-param">hour=self.hour</em>, <em class="sig-param">minute=self.minute</em>, <em class="sig-param">second=self.second</em>, <em class="sig-param">microsecond=self.microsecond</em>, <em class="sig-param">tzinfo=self.tzinfo</em>, <em class="sig-param">*</em>, <em class="sig-param">fold=0</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.replace" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个具有同样属性值的 datetime，除非通过任何关键字参数为某些属性指定了新值。 请注意可以通过指定 <code class="docutils literal notranslate"><span class="pre">tzinfo=None</span></code> 来从一个感知型 datetime 创建一个简单型 datetime 而不必转换日期和时间数据。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.6 新版功能: </span>增加了 <code class="docutils literal notranslate"><span class="pre">fold</span></code> 参数。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.astimezone">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">astimezone</code><span class="sig-paren">(</span><em class="sig-param">tz=None</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.astimezone" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个具有新的 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性 <em>tz</em> 的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象，并会调整日期和时间数据使得结果对应的 UTC 时间与 <em>self</em> 相同，但为 <em>tz</em> 时区的本地时间。</p>
|
||
<p>如果给出了 <em>tz</em>，则它必须是一个 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类的实例，并且其 <a class="reference internal" href="#datetime.datetime.utcoffset" title="datetime.datetime.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 和 <a class="reference internal" href="#datetime.datetime.dst" title="datetime.datetime.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 方法不可返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>。 如果 <em>self</em> 为简单型，它会被假定为基于系统时区表示的时间。</p>
|
||
<p>如果调用时不传入参数 (或传入 <code class="docutils literal notranslate"><span class="pre">tz=None</span></code>) 则将假定目标时区为系统的本地时区。 转换后 datetime 实例的 <code class="docutils literal notranslate"><span class="pre">.tzinfo</span></code> 属性将被设为一个 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 实例，时区名称和时差值将从 OS 获取。</p>
|
||
<p>如果 <code class="docutils literal notranslate"><span class="pre">self.tzinfo</span></code> 为 <em>tz</em>，<code class="docutils literal notranslate"><span class="pre">self.astimezone(tz)</span></code> 等于 <em>self</em>: 不会对日期或时间数据进行调整。 否则结果为 <em>tz</em> 时区的本地时间，代表的 UTC 时间与 <em>self</em> 相同：在 <code class="docutils literal notranslate"><span class="pre">astz</span> <span class="pre">=</span> <span class="pre">dt.astimezone(tz)</span></code> 之后，<code class="docutils literal notranslate"><span class="pre">astz</span> <span class="pre">-</span> <span class="pre">astz.utcoffset()</span></code> 将具有与 <code class="docutils literal notranslate"><span class="pre">dt</span> <span class="pre">-</span> <span class="pre">dt.utcoffset()</span></code> 相同的日期和时间数据。</p>
|
||
<p>如果你只是想要附加一个时区对象 <em>tz</em> 到一个 datetime 对象 <em>dt</em> 而不调整日期和时间数据，请使用 <code class="docutils literal notranslate"><span class="pre">dt.replace(tzinfo=tz)</span></code>。 如果你只想从一个感知型 datetime 对象 <em>dt</em> 移除时区对象，请使用 <code class="docutils literal notranslate"><span class="pre">dt.replace(tzinfo=None)</span></code>。</p>
|
||
<p>请注意默认的 <a class="reference internal" href="#datetime.tzinfo.fromutc" title="datetime.tzinfo.fromutc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tzinfo.fromutc()</span></code></a> 方法在 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 的子类中可以被重写，从而影响 <a class="reference internal" href="#datetime.datetime.astimezone" title="datetime.datetime.astimezone"><code class="xref py py-meth docutils literal notranslate"><span class="pre">astimezone()</span></code></a> 的返回结果。 如果忽略出错的情况，<a class="reference internal" href="#datetime.datetime.astimezone" title="datetime.datetime.astimezone"><code class="xref py py-meth docutils literal notranslate"><span class="pre">astimezone()</span></code></a> 的行为就类似于:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">astimezone</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tz</span><span class="p">):</span>
|
||
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">tzinfo</span> <span class="ow">is</span> <span class="n">tz</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="bp">self</span>
|
||
<span class="c1"># Convert self to UTC, and attach the new time zone object.</span>
|
||
<span class="n">utc</span> <span class="o">=</span> <span class="p">(</span><span class="bp">self</span> <span class="o">-</span> <span class="bp">self</span><span class="o">.</span><span class="n">utcoffset</span><span class="p">())</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">tzinfo</span><span class="o">=</span><span class="n">tz</span><span class="p">)</span>
|
||
<span class="c1"># Convert from UTC to tz's local time.</span>
|
||
<span class="k">return</span> <span class="n">tz</span><span class="o">.</span><span class="n">fromutc</span><span class="p">(</span><span class="n">utc</span><span class="p">)</span>
|
||
</pre></div>
|
||
</div>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.3 版更改: </span><em>tz</em> 现在可以被省略。</p>
|
||
</div>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.6 版更改: </span><a class="reference internal" href="#datetime.datetime.astimezone" title="datetime.datetime.astimezone"><code class="xref py py-meth docutils literal notranslate"><span class="pre">astimezone()</span></code></a> 方法可以由简单型实例调用，这将假定其表示本地时间。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.utcoffset">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">utcoffset</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.utcoffset" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>如果 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，则返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>，否则返回 <code class="docutils literal notranslate"><span class="pre">self.tzinfo.utcoffset(self)</span></code>，并且在后者不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或者一个幅度小于一天的 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象时将引发异常。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>UTC 时差不再限制为一个整数分钟值。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.dst">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">dst</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.dst" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>如果 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，则返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>，否则返回 <code class="docutils literal notranslate"><span class="pre">self.tzinfo.dst(self)</span></code>，并且在后者不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或者一个幅度小于一天的 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象时将引发异常。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>DST 差值不再限制为一个整数分钟值。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.tzname">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">tzname</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.tzname" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>如果 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，则返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>，否则返回 <code class="docutils literal notranslate"><span class="pre">self.tzinfo.tzname(self)</span></code>，如果后者不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或者一个字符串对象则将引发异常。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.timetuple">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">timetuple</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.timetuple" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个 <a class="reference internal" href="time.html#time.struct_time" title="time.struct_time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time.struct_time</span></code></a>，即 <a class="reference internal" href="time.html#time.localtime" title="time.localtime"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.localtime()</span></code></a> 所返回的类型。</p>
|
||
<p><code class="docutils literal notranslate"><span class="pre">d.timetuple()</span></code> 等价于:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">time</span><span class="o">.</span><span class="n">struct_time</span><span class="p">((</span><span class="n">d</span><span class="o">.</span><span class="n">year</span><span class="p">,</span> <span class="n">d</span><span class="o">.</span><span class="n">month</span><span class="p">,</span> <span class="n">d</span><span class="o">.</span><span class="n">day</span><span class="p">,</span>
|
||
<span class="n">d</span><span class="o">.</span><span class="n">hour</span><span class="p">,</span> <span class="n">d</span><span class="o">.</span><span class="n">minute</span><span class="p">,</span> <span class="n">d</span><span class="o">.</span><span class="n">second</span><span class="p">,</span>
|
||
<span class="n">d</span><span class="o">.</span><span class="n">weekday</span><span class="p">(),</span> <span class="n">yday</span><span class="p">,</span> <span class="n">dst</span><span class="p">))</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>其中 <code class="docutils literal notranslate"><span class="pre">yday</span> <span class="pre">=</span> <span class="pre">d.toordinal()</span> <span class="pre">-</span> <span class="pre">date(d.year,</span> <span class="pre">1,</span> <span class="pre">1).toordinal()</span> <span class="pre">+</span> <span class="pre">1</span></code> 是日期在当前年份中的序号，起始序号 <code class="docutils literal notranslate"><span class="pre">1</span></code> 表示 1 月 1 日。 结果的 <code class="xref py py-attr docutils literal notranslate"><span class="pre">tm_isdst</span></code> 旗标的设定会依据 <a class="reference internal" href="#datetime.datetime.dst" title="datetime.datetime.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 方法：如果 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或 <a class="reference internal" href="#datetime.datetime.dst" title="datetime.datetime.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>，则 <code class="xref py py-attr docutils literal notranslate"><span class="pre">tm_isdst</span></code> 将设为 <code class="docutils literal notranslate"><span class="pre">-1</span></code>；否则如果 <a class="reference internal" href="#datetime.datetime.dst" title="datetime.datetime.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 返回一个非零值，则 <code class="xref py py-attr docutils literal notranslate"><span class="pre">tm_isdst</span></code> 将设为 <code class="docutils literal notranslate"><span class="pre">1</span></code>；在其他情况下 <code class="xref py py-attr docutils literal notranslate"><span class="pre">tm_isdst</span></code> 将设为 <code class="docutils literal notranslate"><span class="pre">0</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.utctimetuple">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">utctimetuple</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.utctimetuple" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>如果 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 实例 <em>d</em> 为简单型，这类似于 <code class="docutils literal notranslate"><span class="pre">d.timetuple()</span></code>，不同之处在于 <code class="xref py py-attr docutils literal notranslate"><span class="pre">tm_isdst</span></code> 会强制设为 0，无论 <code class="docutils literal notranslate"><span class="pre">d.dst()</span></code> 返回什么结果。 DST 对于 UTC 时间永远无效。</p>
|
||
<p>如果 <em>d</em> 为感知型， <em>d</em> 会通过减去 <code class="docutils literal notranslate"><span class="pre">d.utcoffset()</span></code> 来标准化为 UTC 时间，并返回该标准化时间所对应的 <a class="reference internal" href="time.html#time.struct_time" title="time.struct_time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time.struct_time</span></code></a>。 <code class="xref py py-attr docutils literal notranslate"><span class="pre">tm_isdst</span></code> 会强制设为 0。 请注意如果 <em>d</em>.year 为 <code class="docutils literal notranslate"><span class="pre">MINYEAR</span></code> 或 <code class="docutils literal notranslate"><span class="pre">MAXYEAR</span></code> 并且 UTC 调整超出一年的边界则可能引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a>。</p>
|
||
<div class="admonition warning">
|
||
<p class="admonition-title">警告</p>
|
||
<p>由于简单型 <code class="docutils literal notranslate"><span class="pre">datetime</span></code> 对象会被许多 <code class="docutils literal notranslate"><span class="pre">datetime</span></code> 方法当作本地时间来处理，最好是使用感知型日期时间来表示 UTC 时间；因此，使用 <code class="docutils literal notranslate"><span class="pre">utcfromtimetuple</span></code> 可能会给出误导性的结果。 如果你有一个表示 UTC 的简单型 <code class="docutils literal notranslate"><span class="pre">datetime</span></code>，请使用 <code class="docutils literal notranslate"><span class="pre">datetime.replace(tzinfo=timezone.utc)</span></code> 将其改为感知型，这样你才能使用 <a class="reference internal" href="#datetime.datetime.timetuple" title="datetime.datetime.timetuple"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.timetuple()</span></code></a>。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.toordinal">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">toordinal</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.toordinal" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回日期的预期格列高利历序号。 与 <code class="docutils literal notranslate"><span class="pre">self.date().toordinal()</span></code> 相同。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.timestamp">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">timestamp</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.timestamp" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回对应于 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 实例的 POSIX 时间戳。 此返回值是与 <a class="reference internal" href="time.html#time.time" title="time.time"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.time()</span></code></a> 返回值类似的 <a class="reference internal" href="functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate"><span class="pre">float</span></code></a> 对象。</p>
|
||
<p>简单型 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 实例会假定为代表本地时间，并且此方法依赖于平台的 C <code class="xref c c-func docutils literal notranslate"><span class="pre">mktime()</span></code> 函数来执行转换。 由于在许多平台上 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 支持的范围比 <code class="xref c c-func docutils literal notranslate"><span class="pre">mktime()</span></code> 更广，对于极其遥远的过去或未来此方法可能引发 <a class="reference internal" href="exceptions.html#OverflowError" title="OverflowError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">OverflowError</span></code></a>。</p>
|
||
<p>对于感知型 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 实例，返回值的计算方式为:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="p">(</span><span class="n">dt</span> <span class="o">-</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1970</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">))</span><span class="o">.</span><span class="n">total_seconds</span><span class="p">()</span>
|
||
</pre></div>
|
||
</div>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.3 新版功能.</span></p>
|
||
</div>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.6 版更改: </span><a class="reference internal" href="#datetime.datetime.timestamp" title="datetime.datetime.timestamp"><code class="xref py py-meth docutils literal notranslate"><span class="pre">timestamp()</span></code></a> 方法使用 <a class="reference internal" href="#datetime.datetime.fold" title="datetime.datetime.fold"><code class="xref py py-attr docutils literal notranslate"><span class="pre">fold</span></code></a> 属性来消除重复间隔中的时间歧义。</p>
|
||
</div>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">注解</p>
|
||
<p>没有一个方法能直接从表示 UTC 时间的简单型 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 实例获取 POSIX 时间戳。 如果你的应用程序使用此惯例并且你的系统时区不是设为 UTC，你可以通过提供 <code class="docutils literal notranslate"><span class="pre">tzinfo=timezone.utc</span></code> 来获取 POSIX 时间戳:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">timestamp</span> <span class="o">=</span> <span class="n">dt</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">tzinfo</span><span class="o">=</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span><span class="o">.</span><span class="n">timestamp</span><span class="p">()</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>或者通过直接计算时间戳:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">timestamp</span> <span class="o">=</span> <span class="p">(</span><span class="n">dt</span> <span class="o">-</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1970</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">))</span> <span class="o">/</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">seconds</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
|
||
</pre></div>
|
||
</div>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.weekday">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">weekday</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.weekday" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个整数代表星期几，星期一为 0，星期天为 6。 相当于 <code class="docutils literal notranslate"><span class="pre">self.date().weekday()</span></code>。 另请参阅 <a class="reference internal" href="#datetime.datetime.isoweekday" title="datetime.datetime.isoweekday"><code class="xref py py-meth docutils literal notranslate"><span class="pre">isoweekday()</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.isoweekday">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">isoweekday</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.isoweekday" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个整数代表星期几，星期一为 1，星期天为 7。 相当于 <code class="docutils literal notranslate"><span class="pre">self.date().isoweekday()</span></code>。 另请参阅 <a class="reference internal" href="#datetime.datetime.weekday" title="datetime.datetime.weekday"><code class="xref py py-meth docutils literal notranslate"><span class="pre">weekday()</span></code></a>, <a class="reference internal" href="#datetime.datetime.isocalendar" title="datetime.datetime.isocalendar"><code class="xref py py-meth docutils literal notranslate"><span class="pre">isocalendar()</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.isocalendar">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">isocalendar</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.isocalendar" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个 3 元组 (ISO 年份, ISO 周序号, ISO 周日期)。 等同于 <code class="docutils literal notranslate"><span class="pre">self.date().isocalendar()</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.isoformat">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">isoformat</code><span class="sig-paren">(</span><em class="sig-param">sep='T'</em>, <em class="sig-param">timespec='auto'</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.isoformat" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个以 ISO 8601 格式表示的日期和时间字符串：</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">YYYY-MM-DDTHH:MM:SS.ffffff</span></code>，如果 <a class="reference internal" href="#datetime.datetime.microsecond" title="datetime.datetime.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 不为 0</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">YYYY-MM-DDTHH:MM:SS</span></code>，如果 <a class="reference internal" href="#datetime.datetime.microsecond" title="datetime.datetime.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 为 0</p></li>
|
||
</ul>
|
||
<p>如果 <a class="reference internal" href="#datetime.datetime.utcoffset" title="datetime.datetime.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 返回值不为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，则添加一个字符串来给出 UTC 时差：</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">YYYY-MM-DDTHH:MM:SS.ffffff+HH:MM[:SS[.ffffff]]</span></code>，如果 <a class="reference internal" href="#datetime.datetime.microsecond" title="datetime.datetime.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 不为 0</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">YYYY-MM-DDTHH:MM:SS+HH:MM[:SS[.ffffff]]</span></code>，如果 <a class="reference internal" href="#datetime.datetime.microsecond" title="datetime.datetime.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 为 0</p></li>
|
||
</ul>
|
||
<p>示例:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">datetime</span><span class="p">,</span> <span class="n">timezone</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="p">(</span><span class="mi">2019</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="mi">18</span><span class="p">,</span> <span class="mi">15</span><span class="p">,</span> <span class="mi">17</span><span class="p">,</span> <span class="mi">8</span><span class="p">,</span> <span class="mi">132263</span><span class="p">)</span><span class="o">.</span><span class="n">isoformat</span><span class="p">()</span>
|
||
<span class="go">'2019-05-18T15:17:08.132263'</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="p">(</span><span class="mi">2019</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="mi">18</span><span class="p">,</span> <span class="mi">15</span><span class="p">,</span> <span class="mi">17</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span><span class="o">.</span><span class="n">isoformat</span><span class="p">()</span>
|
||
<span class="go">'2019-05-18T15:17:00+00:00'</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>可选参数 <em>sep</em> (默认为 <code class="docutils literal notranslate"><span class="pre">'T'</span></code>) 为单个分隔字符，会被放在结果的日期和时间两部分之间。 例如:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">tzinfo</span><span class="p">,</span> <span class="n">timedelta</span><span class="p">,</span> <span class="n">datetime</span>
|
||
<span class="gp">>>> </span><span class="k">class</span> <span class="nc">TZ</span><span class="p">(</span><span class="n">tzinfo</span><span class="p">):</span>
|
||
<span class="gp">... </span><span class="w"> </span><span class="sd">"""A time zone with an arbitrary, constant -06:39 offset."""</span>
|
||
<span class="gp">... </span> <span class="k">def</span> <span class="nf">utcoffset</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="gp">... </span> <span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=-</span><span class="mi">6</span><span class="p">,</span> <span class="n">minutes</span><span class="o">=-</span><span class="mi">39</span><span class="p">)</span>
|
||
<span class="gp">...</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="p">(</span><span class="mi">2002</span><span class="p">,</span> <span class="mi">12</span><span class="p">,</span> <span class="mi">25</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">TZ</span><span class="p">())</span><span class="o">.</span><span class="n">isoformat</span><span class="p">(</span><span class="s1">' '</span><span class="p">)</span>
|
||
<span class="go">'2002-12-25 00:00:00-06:39'</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="p">(</span><span class="mi">2009</span><span class="p">,</span> <span class="mi">11</span><span class="p">,</span> <span class="mi">27</span><span class="p">,</span> <span class="n">microsecond</span><span class="o">=</span><span class="mi">100</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">TZ</span><span class="p">())</span><span class="o">.</span><span class="n">isoformat</span><span class="p">()</span>
|
||
<span class="go">'2009-11-27T00:00:00.000100-06:39'</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>可选参数 <em>timespec</em> 要包含的额外时间组件值 (默认为 <code class="docutils literal notranslate"><span class="pre">'auto'</span></code>)。它可以是以下值之一：</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'auto'</span></code>: 如果 <a class="reference internal" href="#datetime.datetime.microsecond" title="datetime.datetime.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 为 0 则与 <code class="docutils literal notranslate"><span class="pre">'seconds'</span></code> 相同，否则与 <code class="docutils literal notranslate"><span class="pre">'microseconds'</span></code> 相同。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'hours'</span></code>: 以两个数码的 <code class="docutils literal notranslate"><span class="pre">HH</span></code> 格式 包含 <a class="reference internal" href="#datetime.datetime.hour" title="datetime.datetime.hour"><code class="xref py py-attr docutils literal notranslate"><span class="pre">hour</span></code></a>。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'minutes'</span></code>: 以 <code class="docutils literal notranslate"><span class="pre">HH:MM</span></code> 格式包含 <a class="reference internal" href="#datetime.datetime.hour" title="datetime.datetime.hour"><code class="xref py py-attr docutils literal notranslate"><span class="pre">hour</span></code></a> 和 <a class="reference internal" href="#datetime.datetime.minute" title="datetime.datetime.minute"><code class="xref py py-attr docutils literal notranslate"><span class="pre">minute</span></code></a>。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'seconds'</span></code>: 以 <code class="docutils literal notranslate"><span class="pre">HH:MM:SS</span></code> 格式包含 <a class="reference internal" href="#datetime.datetime.hour" title="datetime.datetime.hour"><code class="xref py py-attr docutils literal notranslate"><span class="pre">hour</span></code></a>, <a class="reference internal" href="#datetime.datetime.minute" title="datetime.datetime.minute"><code class="xref py py-attr docutils literal notranslate"><span class="pre">minute</span></code></a> 和 <a class="reference internal" href="#datetime.datetime.second" title="datetime.datetime.second"><code class="xref py py-attr docutils literal notranslate"><span class="pre">second</span></code></a>。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'milliseconds'</span></code>: 包含完整时间，但将秒值的小数部分截断至毫秒。 格式为 <code class="docutils literal notranslate"><span class="pre">HH:MM:SS.sss</span></code>。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'microseconds'</span></code>: 以 <code class="docutils literal notranslate"><span class="pre">HH:MM:SS.ffffff</span></code> 格式包含完整时间。</p></li>
|
||
</ul>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">注解</p>
|
||
<p>排除掉的时间部分将被截断，而不是被舍入。</p>
|
||
</div>
|
||
<p>对于无效的 <em>timespec</em> 参数将引发 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">datetime</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="o">.</span><span class="n">now</span><span class="p">()</span><span class="o">.</span><span class="n">isoformat</span><span class="p">(</span><span class="n">timespec</span><span class="o">=</span><span class="s1">'minutes'</span><span class="p">)</span>
|
||
<span class="go">'2002-12-25T00:00'</span>
|
||
<span class="gp">>>> </span><span class="n">dt</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">2015</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">12</span><span class="p">,</span> <span class="mi">30</span><span class="p">,</span> <span class="mi">59</span><span class="p">,</span> <span class="mi">0</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">dt</span><span class="o">.</span><span class="n">isoformat</span><span class="p">(</span><span class="n">timespec</span><span class="o">=</span><span class="s1">'microseconds'</span><span class="p">)</span>
|
||
<span class="go">'2015-01-01T12:30:59.000000'</span>
|
||
</pre></div>
|
||
</div>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.6 新版功能: </span>增加了 <em>timespec</em> 参数。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.__str__">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">__str__</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.__str__" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>对于 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 实例 <em>d</em>，<code class="docutils literal notranslate"><span class="pre">str(d)</span></code> 等价于 <code class="docutils literal notranslate"><span class="pre">d.isoformat('</span> <span class="pre">')</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.ctime">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">ctime</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.ctime" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个表示日期和时间的字符串:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">datetime</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="p">(</span><span class="mi">2002</span><span class="p">,</span> <span class="mi">12</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">,</span> <span class="mi">40</span><span class="p">)</span><span class="o">.</span><span class="n">ctime</span><span class="p">()</span>
|
||
<span class="go">'Wed Dec 4 20:30:40 2002'</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>输出字符串将 <em>并不</em> 包括时区信息，无论输入的是感知型还是简单型。</p>
|
||
<p><code class="docutils literal notranslate"><span class="pre">d.ctime()</span></code> 等效于:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">time</span><span class="o">.</span><span class="n">ctime</span><span class="p">(</span><span class="n">time</span><span class="o">.</span><span class="n">mktime</span><span class="p">(</span><span class="n">d</span><span class="o">.</span><span class="n">timetuple</span><span class="p">()))</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>在原生 C <code class="xref c c-func docutils literal notranslate"><span class="pre">ctime()</span></code> 函数遵循 C 标准的平台上 (<a class="reference internal" href="time.html#time.ctime" title="time.ctime"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.ctime()</span></code></a> 会发起对该函数的调用，但 <a class="reference internal" href="#datetime.datetime.ctime" title="datetime.datetime.ctime"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.ctime()</span></code></a> 并不会) 。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.strftime">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">strftime</code><span class="sig-paren">(</span><em class="sig-param">format</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.strftime" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个由显式格式字符串所指明的代表日期和时间的字符串，要获取格式指令的完整列表，请参阅 <a class="reference internal" href="#strftime-strptime-behavior"><span class="std std-ref">strftime() 和 strptime() 的行为</span></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.datetime.__format__">
|
||
<code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">__format__</code><span class="sig-paren">(</span><em class="sig-param">format</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.datetime.__format__" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>与 <a class="reference internal" href="#datetime.datetime.strftime" title="datetime.datetime.strftime"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.strftime()</span></code></a> 相同。 此方法使得为 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象指定以 <a class="reference internal" href="../reference/lexical_analysis.html#f-strings"><span class="std std-ref">格式化字符串字面值</span></a> 表示的格式化字符串以及使用 <a class="reference internal" href="stdtypes.html#str.format" title="str.format"><code class="xref py py-meth docutils literal notranslate"><span class="pre">str.format()</span></code></a> 进行格式化成为可能。 要获取格式指令的完整列表，请参阅 <a class="reference internal" href="#strftime-strptime-behavior"><span class="std std-ref">strftime() 和 strptime() 的行为</span></a>。</p>
|
||
</dd></dl>
|
||
|
||
<section id="examples-of-usage-datetime">
|
||
<h3>用法示例: <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a><a class="headerlink" href="#examples-of-usage-datetime" title="永久链接至标题">¶</a></h3>
|
||
<p>使用 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象的例子：</p>
|
||
<div class="highlight-pycon3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">datetime</span><span class="p">,</span> <span class="n">date</span><span class="p">,</span> <span class="n">time</span><span class="p">,</span> <span class="n">timezone</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Using datetime.combine()</span>
|
||
<span class="gp">>>> </span><span class="n">d</span> <span class="o">=</span> <span class="n">date</span><span class="p">(</span><span class="mi">2005</span><span class="p">,</span> <span class="mi">7</span><span class="p">,</span> <span class="mi">14</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">t</span> <span class="o">=</span> <span class="n">time</span><span class="p">(</span><span class="mi">12</span><span class="p">,</span> <span class="mi">30</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="o">.</span><span class="n">combine</span><span class="p">(</span><span class="n">d</span><span class="p">,</span> <span class="n">t</span><span class="p">)</span>
|
||
<span class="go">datetime.datetime(2005, 7, 14, 12, 30)</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Using datetime.now()</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="o">.</span><span class="n">now</span><span class="p">()</span>
|
||
<span class="go">datetime.datetime(2007, 12, 6, 16, 29, 43, 79043) # GMT +1</span>
|
||
<span class="gp">>>> </span><span class="n">datetime</span><span class="o">.</span><span class="n">now</span><span class="p">(</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span>
|
||
<span class="go">datetime.datetime(2007, 12, 6, 15, 29, 43, 79060, tzinfo=datetime.timezone.utc)</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Using datetime.strptime()</span>
|
||
<span class="gp">>>> </span><span class="n">dt</span> <span class="o">=</span> <span class="n">datetime</span><span class="o">.</span><span class="n">strptime</span><span class="p">(</span><span class="s2">"21/11/06 16:30"</span><span class="p">,</span> <span class="s2">"</span><span class="si">%d</span><span class="s2">/%m/%y %H:%M"</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">dt</span>
|
||
<span class="go">datetime.datetime(2006, 11, 21, 16, 30)</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Using datetime.timetuple() to get tuple of all attributes</span>
|
||
<span class="gp">>>> </span><span class="n">tt</span> <span class="o">=</span> <span class="n">dt</span><span class="o">.</span><span class="n">timetuple</span><span class="p">()</span>
|
||
<span class="gp">>>> </span><span class="k">for</span> <span class="n">it</span> <span class="ow">in</span> <span class="n">tt</span><span class="p">:</span>
|
||
<span class="gp">... </span> <span class="nb">print</span><span class="p">(</span><span class="n">it</span><span class="p">)</span>
|
||
<span class="gp">...</span>
|
||
<span class="go">2006 # year</span>
|
||
<span class="go">11 # month</span>
|
||
<span class="go">21 # day</span>
|
||
<span class="go">16 # hour</span>
|
||
<span class="go">30 # minute</span>
|
||
<span class="go">0 # second</span>
|
||
<span class="go">1 # weekday (0 = Monday)</span>
|
||
<span class="go">325 # number of days since 1st January</span>
|
||
<span class="go">-1 # dst - method tzinfo.dst() returned None</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Date in ISO format</span>
|
||
<span class="gp">>>> </span><span class="n">ic</span> <span class="o">=</span> <span class="n">dt</span><span class="o">.</span><span class="n">isocalendar</span><span class="p">()</span>
|
||
<span class="gp">>>> </span><span class="k">for</span> <span class="n">it</span> <span class="ow">in</span> <span class="n">ic</span><span class="p">:</span>
|
||
<span class="gp">... </span> <span class="nb">print</span><span class="p">(</span><span class="n">it</span><span class="p">)</span>
|
||
<span class="gp">...</span>
|
||
<span class="go">2006 # ISO year</span>
|
||
<span class="go">47 # ISO week</span>
|
||
<span class="go">2 # ISO weekday</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Formatting a datetime</span>
|
||
<span class="gp">>>> </span><span class="n">dt</span><span class="o">.</span><span class="n">strftime</span><span class="p">(</span><span class="s2">"%A, </span><span class="si">%d</span><span class="s2">. %B %Y %I:%M%p"</span><span class="p">)</span>
|
||
<span class="go">'Tuesday, 21. November 2006 04:30PM'</span>
|
||
<span class="gp">>>> </span><span class="s1">'The </span><span class="si">{1}</span><span class="s1"> is {0:</span><span class="si">%d</span><span class="s1">}, the </span><span class="si">{2}</span><span class="s1"> is {0:%B}, the </span><span class="si">{3}</span><span class="s1"> is {0:%I:%M%p}.'</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">dt</span><span class="p">,</span> <span class="s2">"day"</span><span class="p">,</span> <span class="s2">"month"</span><span class="p">,</span> <span class="s2">"time"</span><span class="p">)</span>
|
||
<span class="go">'The day is 21, the month is November, the time is 04:30PM.'</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>以下示例定义了一个 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类，它捕获 Kabul, Afghanistan 时区的信息，该时区使用 +4 UTC 直到 1945 年，之后则使用 +4:30 UTC:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">timedelta</span><span class="p">,</span> <span class="n">datetime</span><span class="p">,</span> <span class="n">tzinfo</span><span class="p">,</span> <span class="n">timezone</span>
|
||
|
||
<span class="k">class</span> <span class="nc">KabulTz</span><span class="p">(</span><span class="n">tzinfo</span><span class="p">):</span>
|
||
<span class="c1"># Kabul used +4 until 1945, when they moved to +4:30</span>
|
||
<span class="n">UTC_MOVE_DATE</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1944</span><span class="p">,</span> <span class="mi">12</span><span class="p">,</span> <span class="mi">31</span><span class="p">,</span> <span class="mi">20</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">utcoffset</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">if</span> <span class="n">dt</span><span class="o">.</span><span class="n">year</span> <span class="o"><</span> <span class="mi">1945</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">4</span><span class="p">)</span>
|
||
<span class="k">elif</span> <span class="p">(</span><span class="mi">1945</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="mi">0</span><span class="p">)</span> <span class="o"><=</span> <span class="n">dt</span><span class="o">.</span><span class="n">timetuple</span><span class="p">()[:</span><span class="mi">5</span><span class="p">]</span> <span class="o"><</span> <span class="p">(</span><span class="mi">1945</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="mi">30</span><span class="p">):</span>
|
||
<span class="c1"># An ambiguous ("imaginary") half-hour range representing</span>
|
||
<span class="c1"># a 'fold' in time due to the shift from +4 to +4:30.</span>
|
||
<span class="c1"># If dt falls in the imaginary range, use fold to decide how</span>
|
||
<span class="c1"># to resolve. See PEP495.</span>
|
||
<span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">4</span><span class="p">,</span> <span class="n">minutes</span><span class="o">=</span><span class="p">(</span><span class="mi">30</span> <span class="k">if</span> <span class="n">dt</span><span class="o">.</span><span class="n">fold</span> <span class="k">else</span> <span class="mi">0</span><span class="p">))</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">4</span><span class="p">,</span> <span class="n">minutes</span><span class="o">=</span><span class="mi">30</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">fromutc</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="c1"># Follow same validations as in datetime.tzinfo</span>
|
||
<span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">dt</span><span class="p">,</span> <span class="n">datetime</span><span class="p">):</span>
|
||
<span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"fromutc() requires a datetime argument"</span><span class="p">)</span>
|
||
<span class="k">if</span> <span class="n">dt</span><span class="o">.</span><span class="n">tzinfo</span> <span class="ow">is</span> <span class="ow">not</span> <span class="bp">self</span><span class="p">:</span>
|
||
<span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"dt.tzinfo is not self"</span><span class="p">)</span>
|
||
|
||
<span class="c1"># A custom implementation is required for fromutc as</span>
|
||
<span class="c1"># the input to this function is a datetime with utc values</span>
|
||
<span class="c1"># but with a tzinfo set to self.</span>
|
||
<span class="c1"># See datetime.astimezone or fromtimestamp.</span>
|
||
<span class="k">if</span> <span class="n">dt</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">tzinfo</span><span class="o">=</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span> <span class="o">>=</span> <span class="bp">self</span><span class="o">.</span><span class="n">UTC_MOVE_DATE</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">dt</span> <span class="o">+</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">4</span><span class="p">,</span> <span class="n">minutes</span><span class="o">=</span><span class="mi">30</span><span class="p">)</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">dt</span> <span class="o">+</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">4</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">dst</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="c1"># Kabul does not observe daylight saving time.</span>
|
||
<span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">tzname</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">if</span> <span class="n">dt</span> <span class="o">>=</span> <span class="bp">self</span><span class="o">.</span><span class="n">UTC_MOVE_DATE</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="s2">"+04:30"</span>
|
||
<span class="k">return</span> <span class="s2">"+04"</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>上述 <code class="docutils literal notranslate"><span class="pre">KabulTz</span></code> 的用法:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">tz1</span> <span class="o">=</span> <span class="n">KabulTz</span><span class="p">()</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Datetime before the change</span>
|
||
<span class="gp">>>> </span><span class="n">dt1</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1900</span><span class="p">,</span> <span class="mi">11</span><span class="p">,</span> <span class="mi">21</span><span class="p">,</span> <span class="mi">16</span><span class="p">,</span> <span class="mi">30</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">tz1</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="n">dt1</span><span class="o">.</span><span class="n">utcoffset</span><span class="p">())</span>
|
||
<span class="go">4:00:00</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Datetime after the change</span>
|
||
<span class="gp">>>> </span><span class="n">dt2</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">2006</span><span class="p">,</span> <span class="mi">6</span><span class="p">,</span> <span class="mi">14</span><span class="p">,</span> <span class="mi">13</span><span class="p">,</span> <span class="mi">0</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">tz1</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="n">dt2</span><span class="o">.</span><span class="n">utcoffset</span><span class="p">())</span>
|
||
<span class="go">4:30:00</span>
|
||
|
||
<span class="gp">>>> </span><span class="c1"># Convert datetime to another time zone</span>
|
||
<span class="gp">>>> </span><span class="n">dt3</span> <span class="o">=</span> <span class="n">dt2</span><span class="o">.</span><span class="n">astimezone</span><span class="p">(</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">dt3</span>
|
||
<span class="go">datetime.datetime(2006, 6, 14, 8, 30, tzinfo=datetime.timezone.utc)</span>
|
||
<span class="gp">>>> </span><span class="n">dt2</span>
|
||
<span class="go">datetime.datetime(2006, 6, 14, 13, 0, tzinfo=KabulTz())</span>
|
||
<span class="gp">>>> </span><span class="n">dt2</span> <span class="o">==</span> <span class="n">dt3</span>
|
||
<span class="go">True</span>
|
||
</pre></div>
|
||
</div>
|
||
</section>
|
||
</section>
|
||
<section id="time-objects">
|
||
<span id="datetime-time"></span><h2><a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象<a class="headerlink" href="#time-objects" title="永久链接至标题">¶</a></h2>
|
||
<p>一个 <a class="reference internal" href="time.html#module-time" title="time: Time access and conversions."><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象代表某日的（本地）时间，它独立于任何特定日期，并可通过 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 对象来调整。</p>
|
||
<dl class="class">
|
||
<dt id="datetime.time">
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">time</code><span class="sig-paren">(</span><em class="sig-param">hour=0</em>, <em class="sig-param">minute=0</em>, <em class="sig-param">second=0</em>, <em class="sig-param">microsecond=0</em>, <em class="sig-param">tzinfo=None</em>, <em class="sig-param">*</em>, <em class="sig-param">fold=0</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>所有参数都是可选的。 <em>tzinfo</em> 可以是 <code class="docutils literal notranslate"><span class="pre">None</span></code>，或者是一个 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类的实例。 其余的参数必须是在下面范围内的整数：</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">hour</span> <span class="pre"><</span> <span class="pre">24</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">minute</span> <span class="pre"><</span> <span class="pre">60</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">second</span> <span class="pre"><</span> <span class="pre">60</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">0</span> <span class="pre"><=</span> <span class="pre">microsecond</span> <span class="pre"><</span> <span class="pre">1000000</span></code>,</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">fold</span> <span class="pre">in</span> <span class="pre">[0,</span> <span class="pre">1]</span></code>.</p></li>
|
||
</ul>
|
||
<p>如果给出一个此范围以外的参数，则会引发 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。 所有参数值默认为 <code class="docutils literal notranslate"><span class="pre">0</span></code>，只有 <em>tzinfo</em> 默认为 <a class="reference internal" href="constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate"><span class="pre">None</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<p>类属性：</p>
|
||
<dl class="attribute">
|
||
<dt id="datetime.time.min">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">min</code><a class="headerlink" href="#datetime.time.min" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>早最的可表示 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a>, <code class="docutils literal notranslate"><span class="pre">time(0,</span> <span class="pre">0,</span> <span class="pre">0,</span> <span class="pre">0)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.time.max">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">max</code><a class="headerlink" href="#datetime.time.max" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>最晚的可表示 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a>, <code class="docutils literal notranslate"><span class="pre">time(23,</span> <span class="pre">59,</span> <span class="pre">59,</span> <span class="pre">999999)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.time.resolution">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">resolution</code><a class="headerlink" href="#datetime.time.resolution" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>两个不相等的 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象之间可能的最小间隔，<code class="docutils literal notranslate"><span class="pre">timedelta(microseconds=1)</span></code>，但是请注意 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象并不支持算术运算。</p>
|
||
</dd></dl>
|
||
|
||
<p>实例属性（只读）：</p>
|
||
<dl class="attribute">
|
||
<dt id="datetime.time.hour">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">hour</code><a class="headerlink" href="#datetime.time.hour" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">range(24)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.time.minute">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">minute</code><a class="headerlink" href="#datetime.time.minute" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">range(60)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.time.second">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">second</code><a class="headerlink" href="#datetime.time.second" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">range(60)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.time.microsecond">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">microsecond</code><a class="headerlink" href="#datetime.time.microsecond" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">range(1000000)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.time.tzinfo">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">tzinfo</code><a class="headerlink" href="#datetime.time.tzinfo" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>作为 tzinfo 参数被传给 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 构造器的对象，如果没有传入值则为 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="attribute">
|
||
<dt id="datetime.time.fold">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">fold</code><a class="headerlink" href="#datetime.time.fold" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>取值范围是 <code class="docutils literal notranslate"><span class="pre">[0,</span> <span class="pre">1]</span></code>。 用于在重复的时间段中消除边界时间歧义。 （当夏令时结束时回拨时钟或由于政治原因导致当明时区的 UTC 时差减少就会出现重复的时间段。） 取值 0 (1) 表示两个时刻早于（晚于）所代表的同一边界时间。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.6 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<p><a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象支持 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 与 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 的比较，当 <em>a</em> 时间在 <em>b</em> 之前时，则认为 <em>a</em> 小于 <em>b</em>。 如果比较的一方是简单型而另一方是感知型，则如果尝试进行顺序比较将引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>。 对于相等比较，简单型实例将永远不等于感知型实例。</p>
|
||
<p>如果两个比较方都是感知型，且具有相同的 <a class="reference internal" href="#datetime.time.tzinfo" title="datetime.time.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性，相同的 <a class="reference internal" href="#datetime.time.tzinfo" title="datetime.time.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性会被忽略并对基本时间值进行比较。 如果两个比较方都是感知型且具有不同的 <a class="reference internal" href="#datetime.time.tzinfo" title="datetime.time.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性，两个比较方将首先通过减去它们的 UTC 时差（从 <code class="docutils literal notranslate"><span class="pre">self.utcoffset()</span></code> 获取）来进行调整。 为了防止将混合类型比较回退为基于对象地址的默认比较，当 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象与不同类型的对象比较时，将会引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>，除非比较运算符是 <code class="docutils literal notranslate"><span class="pre">==</span></code> 或 <code class="docutils literal notranslate"><span class="pre">!=</span></code>。 在后两种情况下将分别返回 <a class="reference internal" href="constants.html#False" title="False"><code class="xref py py-const docutils literal notranslate"><span class="pre">False</span></code></a> 或 <a class="reference internal" href="constants.html#True" title="True"><code class="xref py py-const docutils literal notranslate"><span class="pre">True</span></code></a>。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.3 版更改: </span>感知型和简单型 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 实例之间的相等比较不会引发 <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>。</p>
|
||
</div>
|
||
<p>在布尔运算时，<a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象总是被视为真值。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.5 版更改: </span>在 Python 3.5 之前，如果一个 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象代表 UTC 午夜零时则会被视为假值。 此行为被认为容易引发困惑和错误，因此从 Python 3.5 起已被去除。 详情参见 <a class="reference external" href="https://bugs.python.org/issue?@action=redirect&bpo=13936">bpo-13936</a>。</p>
|
||
</div>
|
||
<p>其他构造方法：</p>
|
||
<dl class="method">
|
||
<dt id="datetime.time.fromisoformat">
|
||
<em class="property">classmethod </em><code class="sig-prename descclassname">time.</code><code class="sig-name descname">fromisoformat</code><span class="sig-paren">(</span><em class="sig-param">time_string</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time.fromisoformat" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回对应于 <a class="reference internal" href="#datetime.time.isoformat" title="datetime.time.isoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">time.isoformat()</span></code></a> 所提供的某种 <em>time_string</em> 格式的 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a>。 特别地，此函数支持以下格式的字符串：</p>
|
||
<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>HH[:MM[:SS[.fff[fff]]]][+HH:MM[:SS[.ffffff]]]
|
||
</pre></div>
|
||
</div>
|
||
<div class="admonition caution">
|
||
<p class="admonition-title">警告</p>
|
||
<p>此方法 <em>并不</em> 支持解析任意 ISO 8601 字符串。 它的目的只是作为 <a class="reference internal" href="#datetime.time.isoformat" title="datetime.time.isoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">time.isoformat()</span></code></a> 的逆操作。</p>
|
||
</div>
|
||
<p>示例:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">time</span>
|
||
<span class="gp">>>> </span><span class="n">time</span><span class="o">.</span><span class="n">fromisoformat</span><span class="p">(</span><span class="s1">'04:23:01'</span><span class="p">)</span>
|
||
<span class="go">datetime.time(4, 23, 1)</span>
|
||
<span class="gp">>>> </span><span class="n">time</span><span class="o">.</span><span class="n">fromisoformat</span><span class="p">(</span><span class="s1">'04:23:01.000384'</span><span class="p">)</span>
|
||
<span class="go">datetime.time(4, 23, 1, 384)</span>
|
||
<span class="gp">>>> </span><span class="n">time</span><span class="o">.</span><span class="n">fromisoformat</span><span class="p">(</span><span class="s1">'04:23:01+04:00'</span><span class="p">)</span>
|
||
<span class="go">datetime.time(4, 23, 1, tzinfo=datetime.timezone(datetime.timedelta(seconds=14400)))</span>
|
||
</pre></div>
|
||
</div>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.7 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<p>实例方法：</p>
|
||
<dl class="method">
|
||
<dt id="datetime.time.replace">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">replace</code><span class="sig-paren">(</span><em class="sig-param">hour=self.hour</em>, <em class="sig-param">minute=self.minute</em>, <em class="sig-param">second=self.second</em>, <em class="sig-param">microsecond=self.microsecond</em>, <em class="sig-param">tzinfo=self.tzinfo</em>, <em class="sig-param">*</em>, <em class="sig-param">fold=0</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time.replace" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个具有同样属性值的 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a>，除非通过任何关键字参数指定了某些属性值。 请注意可以通过指定 <code class="docutils literal notranslate"><span class="pre">tzinfo=None</span></code> 从一个感知型 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 创建一个简单型 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a>，而不必转换时间数据。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.6 新版功能: </span>增加了 <code class="docutils literal notranslate"><span class="pre">fold</span></code> 参数。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.time.isoformat">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">isoformat</code><span class="sig-paren">(</span><em class="sig-param">timespec='auto'</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time.isoformat" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回表示为下列 ISO 8601 格式之一的时间字符串：</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">HH:MM:SS.ffffff</span></code>，如果 <a class="reference internal" href="#datetime.time.microsecond" title="datetime.time.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 不为 0</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">HH:MM:SS</span></code>，如果 <a class="reference internal" href="#datetime.time.microsecond" title="datetime.time.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 为 0</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">HH:MM:SS.ffffff+HH:MM[:SS[.ffffff]]</span></code>，如果 <a class="reference internal" href="#datetime.time.utcoffset" title="datetime.time.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code></p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">HH:MM:SS+HH:MM[:SS[.ffffff]]</span></code>，如果 <a class="reference internal" href="#datetime.time.microsecond" title="datetime.time.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 为 0 并且 <a class="reference internal" href="#datetime.time.utcoffset" title="datetime.time.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code></p></li>
|
||
</ul>
|
||
<p>可选参数 <em>timespec</em> 要包含的额外时间组件值 (默认为 <code class="docutils literal notranslate"><span class="pre">'auto'</span></code>)。它可以是以下值之一：</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'auto'</span></code>: 如果 <a class="reference internal" href="#datetime.time.microsecond" title="datetime.time.microsecond"><code class="xref py py-attr docutils literal notranslate"><span class="pre">microsecond</span></code></a> 为 0 则与 <code class="docutils literal notranslate"><span class="pre">'seconds'</span></code> 相同，否则与 <code class="docutils literal notranslate"><span class="pre">'microseconds'</span></code> 相同。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'hours'</span></code>: 以两个数码的 <code class="docutils literal notranslate"><span class="pre">HH</span></code> 格式 包含 <a class="reference internal" href="#datetime.time.hour" title="datetime.time.hour"><code class="xref py py-attr docutils literal notranslate"><span class="pre">hour</span></code></a>。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'minutes'</span></code>: 以 <code class="docutils literal notranslate"><span class="pre">HH:MM</span></code> 格式包含 <a class="reference internal" href="#datetime.time.hour" title="datetime.time.hour"><code class="xref py py-attr docutils literal notranslate"><span class="pre">hour</span></code></a> 和 <a class="reference internal" href="#datetime.time.minute" title="datetime.time.minute"><code class="xref py py-attr docutils literal notranslate"><span class="pre">minute</span></code></a>。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'seconds'</span></code>: 以 <code class="docutils literal notranslate"><span class="pre">HH:MM:SS</span></code> 格式包含 <a class="reference internal" href="#datetime.time.hour" title="datetime.time.hour"><code class="xref py py-attr docutils literal notranslate"><span class="pre">hour</span></code></a>, <a class="reference internal" href="#datetime.time.minute" title="datetime.time.minute"><code class="xref py py-attr docutils literal notranslate"><span class="pre">minute</span></code></a> 和 <a class="reference internal" href="#datetime.time.second" title="datetime.time.second"><code class="xref py py-attr docutils literal notranslate"><span class="pre">second</span></code></a>。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'milliseconds'</span></code>: 包含完整时间，但将秒值的小数部分截断至毫秒。 格式为 <code class="docutils literal notranslate"><span class="pre">HH:MM:SS.sss</span></code>。</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">'microseconds'</span></code>: 以 <code class="docutils literal notranslate"><span class="pre">HH:MM:SS.ffffff</span></code> 格式包含完整时间。</p></li>
|
||
</ul>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">注解</p>
|
||
<p>排除掉的时间部分将被截断，而不是被舍入。</p>
|
||
</div>
|
||
<p>对于无效的 <em>timespec</em> 参数将引发 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。</p>
|
||
<p>示例:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">time</span>
|
||
<span class="gp">>>> </span><span class="n">time</span><span class="p">(</span><span class="n">hour</span><span class="o">=</span><span class="mi">12</span><span class="p">,</span> <span class="n">minute</span><span class="o">=</span><span class="mi">34</span><span class="p">,</span> <span class="n">second</span><span class="o">=</span><span class="mi">56</span><span class="p">,</span> <span class="n">microsecond</span><span class="o">=</span><span class="mi">123456</span><span class="p">)</span><span class="o">.</span><span class="n">isoformat</span><span class="p">(</span><span class="n">timespec</span><span class="o">=</span><span class="s1">'minutes'</span><span class="p">)</span>
|
||
<span class="go">'12:34'</span>
|
||
<span class="gp">>>> </span><span class="n">dt</span> <span class="o">=</span> <span class="n">time</span><span class="p">(</span><span class="n">hour</span><span class="o">=</span><span class="mi">12</span><span class="p">,</span> <span class="n">minute</span><span class="o">=</span><span class="mi">34</span><span class="p">,</span> <span class="n">second</span><span class="o">=</span><span class="mi">56</span><span class="p">,</span> <span class="n">microsecond</span><span class="o">=</span><span class="mi">0</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="n">dt</span><span class="o">.</span><span class="n">isoformat</span><span class="p">(</span><span class="n">timespec</span><span class="o">=</span><span class="s1">'microseconds'</span><span class="p">)</span>
|
||
<span class="go">'12:34:56.000000'</span>
|
||
<span class="gp">>>> </span><span class="n">dt</span><span class="o">.</span><span class="n">isoformat</span><span class="p">(</span><span class="n">timespec</span><span class="o">=</span><span class="s1">'auto'</span><span class="p">)</span>
|
||
<span class="go">'12:34:56'</span>
|
||
</pre></div>
|
||
</div>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.6 新版功能: </span>增加了 <em>timespec</em> 参数。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.time.__str__">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">__str__</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time.__str__" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>对于时间对象 <em>t</em>, <code class="docutils literal notranslate"><span class="pre">str(t)</span></code> 等价于 <code class="docutils literal notranslate"><span class="pre">t.isoformat()</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.time.strftime">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">strftime</code><span class="sig-paren">(</span><em class="sig-param">format</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time.strftime" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回一个由显式格式字符串所指明的代表时间的字符串。 要获取格式指令的完整列表，请参阅 <a class="reference internal" href="#strftime-strptime-behavior"><span class="std std-ref">strftime() 和 strptime() 的行为</span></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.time.__format__">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">__format__</code><span class="sig-paren">(</span><em class="sig-param">format</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time.__format__" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>与 <a class="reference internal" href="#datetime.time.strftime" title="datetime.time.strftime"><code class="xref py py-meth docutils literal notranslate"><span class="pre">time.strftime()</span></code></a> 相同。 此方法使得为 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象指定以 <a class="reference internal" href="../reference/lexical_analysis.html#f-strings"><span class="std std-ref">格式化字符串字面值</span></a> 表示的格式化字符串以及使用 <a class="reference internal" href="stdtypes.html#str.format" title="str.format"><code class="xref py py-meth docutils literal notranslate"><span class="pre">str.format()</span></code></a> 进行格式化成为可能。 要获取格式指令的完整列表，请参阅 <a class="reference internal" href="#strftime-strptime-behavior"><span class="std std-ref">strftime() 和 strptime() 的行为</span></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.time.utcoffset">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">utcoffset</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time.utcoffset" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>如果 <a class="reference internal" href="#datetime.time.tzinfo" title="datetime.time.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，则返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>，否则返回 <code class="docutils literal notranslate"><span class="pre">self.tzinfo.utcoffset(None)</span></code>，并且在后者不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或一个幅度小于一天的 a <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象时将引发异常。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>UTC 时差不再限制为一个整数分钟值。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.time.dst">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">dst</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time.dst" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>如果 <a class="reference internal" href="#datetime.time.tzinfo" title="datetime.time.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，则返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>，否则返回 <code class="docutils literal notranslate"><span class="pre">self.tzinfo.dst(None)</span></code>，并且在后者不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或者一个幅度小于一天的 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象时将引发异常。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>DST 差值不再限制为一个整数分钟值。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.time.tzname">
|
||
<code class="sig-prename descclassname">time.</code><code class="sig-name descname">tzname</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#datetime.time.tzname" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>如果 <a class="reference internal" href="#datetime.time.tzinfo" title="datetime.time.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，则返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>，否则返回 <code class="docutils literal notranslate"><span class="pre">self.tzinfo.tzname(None)</span></code>，如果后者不返回 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或者一个字符串对象则将引发异常。</p>
|
||
</dd></dl>
|
||
|
||
<section id="examples-of-usage-time">
|
||
<h3>用法示例: <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a><a class="headerlink" href="#examples-of-usage-time" title="永久链接至标题">¶</a></h3>
|
||
<p>使用 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象的例子:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">time</span><span class="p">,</span> <span class="n">tzinfo</span><span class="p">,</span> <span class="n">timedelta</span>
|
||
<span class="gp">>>> </span><span class="k">class</span> <span class="nc">TZ1</span><span class="p">(</span><span class="n">tzinfo</span><span class="p">):</span>
|
||
<span class="gp">... </span> <span class="k">def</span> <span class="nf">utcoffset</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="gp">... </span> <span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
|
||
<span class="gp">... </span> <span class="k">def</span> <span class="nf">dst</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="gp">... </span> <span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span>
|
||
<span class="gp">... </span> <span class="k">def</span> <span class="nf">tzname</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span><span class="n">dt</span><span class="p">):</span>
|
||
<span class="gp">... </span> <span class="k">return</span> <span class="s2">"+01:00"</span>
|
||
<span class="gp">... </span> <span class="k">def</span> <span class="fm">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
|
||
<span class="gp">... </span> <span class="k">return</span> <span class="sa">f</span><span class="s2">"</span><span class="si">{</span><span class="bp">self</span><span class="o">.</span><span class="vm">__class__</span><span class="o">.</span><span class="vm">__name__</span><span class="si">}</span><span class="s2">()"</span>
|
||
<span class="gp">...</span>
|
||
<span class="gp">>>> </span><span class="n">t</span> <span class="o">=</span> <span class="n">time</span><span class="p">(</span><span class="mi">12</span><span class="p">,</span> <span class="mi">10</span><span class="p">,</span> <span class="mi">30</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">TZ1</span><span class="p">())</span>
|
||
<span class="gp">>>> </span><span class="n">t</span>
|
||
<span class="go">datetime.time(12, 10, 30, tzinfo=TZ1())</span>
|
||
<span class="gp">>>> </span><span class="n">t</span><span class="o">.</span><span class="n">isoformat</span><span class="p">()</span>
|
||
<span class="go">'12:10:30+01:00'</span>
|
||
<span class="gp">>>> </span><span class="n">t</span><span class="o">.</span><span class="n">dst</span><span class="p">()</span>
|
||
<span class="go">datetime.timedelta(0)</span>
|
||
<span class="gp">>>> </span><span class="n">t</span><span class="o">.</span><span class="n">tzname</span><span class="p">()</span>
|
||
<span class="go">'+01:00'</span>
|
||
<span class="gp">>>> </span><span class="n">t</span><span class="o">.</span><span class="n">strftime</span><span class="p">(</span><span class="s2">"%H:%M:%S %Z"</span><span class="p">)</span>
|
||
<span class="go">'12:10:30 +01:00'</span>
|
||
<span class="gp">>>> </span><span class="s1">'The </span><span class="si">{}</span><span class="s1"> is {:%H:%M}.'</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="s2">"time"</span><span class="p">,</span> <span class="n">t</span><span class="p">)</span>
|
||
<span class="go">'The time is 12:10.'</span>
|
||
</pre></div>
|
||
</div>
|
||
</section>
|
||
</section>
|
||
<section id="tzinfo-objects">
|
||
<span id="datetime-tzinfo"></span><h2><a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 对象<a class="headerlink" href="#tzinfo-objects" title="永久链接至标题">¶</a></h2>
|
||
<dl class="class">
|
||
<dt id="datetime.tzinfo">
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">tzinfo</code><a class="headerlink" href="#datetime.tzinfo" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>这是一个抽象基类，也就是说该类不应被直接实例化。 请定义 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 的子类来捕获有关特定时区的信息。</p>
|
||
<p><a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 的（某个实体子类）的实例可以被传给 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 和 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象的构造器。 这些对象会将它们的属性视为对应于本地时间，并且 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 对象支持展示本地时间与 UTC 的差值、时区名称以及 DST 差值的方法，都是与传给它们的日期或时间对象的相对值。</p>
|
||
<p>你需要派生一个实体子类，并且（至少）提供你使用 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 方法所需要的标准 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 方法的实现。 <a class="reference internal" href="#module-datetime" title="datetime: Basic date and time types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code></a> 模块提供了 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a>，这是 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 的一个简单实体子类，它能以与 UTC 的固定差值来表示不同的时区，例如 UTC 本身或北美的 EST 和 EDT。</p>
|
||
<p>对于封存操作的特殊要求：一个 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类必须具有可不带参数调用的 <a class="reference internal" href="../reference/datamodel.html#object.__init__" title="object.__init__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__init__()</span></code></a> 方法，否则它虽然可以被封存，但可能无法再次解封。 这是个技术性要求，在未来可能会被取消。</p>
|
||
<p>一个 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 的实体子类可能需要实现以下方法。 具体需要实现的方法取决于感知型 <a class="reference internal" href="#module-datetime" title="datetime: Basic date and time types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象如何使用它。 如果有疑问，可以简单地全都实现。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.tzinfo.utcoffset">
|
||
<code class="sig-prename descclassname">tzinfo.</code><code class="sig-name descname">utcoffset</code><span class="sig-paren">(</span><em class="sig-param">dt</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.tzinfo.utcoffset" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>将本地时间与 UTC 时差返回为一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象，如果本地时区在 UTC 以东则为正值。 如果本地时区在 UTC 以西则为负值。</p>
|
||
<p>这表示与 UTC 的 <em>总计</em> 时差；举例来说，如果一个 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 对象同时代表时区和 DST 调整，则 <a class="reference internal" href="#datetime.tzinfo.utcoffset" title="datetime.tzinfo.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 应当返回两者的和。 如果 UTC 时差不确定则返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>。 在其他情况下返回值必须为一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象，其取值严格限制于 <code class="docutils literal notranslate"><span class="pre">-timedelta(hours=24)</span></code> 和 <code class="docutils literal notranslate"><span class="pre">timedelta(hours=24)</span></code> 之间（差值的幅度必须小于一天）。 大多数 <a class="reference internal" href="#datetime.tzinfo.utcoffset" title="datetime.tzinfo.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 的实现看起来可能像是以下两者之一:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">return</span> <span class="n">CONSTANT</span> <span class="c1"># fixed-offset class</span>
|
||
<span class="k">return</span> <span class="n">CONSTANT</span> <span class="o">+</span> <span class="bp">self</span><span class="o">.</span><span class="n">dst</span><span class="p">(</span><span class="n">dt</span><span class="p">)</span> <span class="c1"># daylight-aware class</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>如果 <a class="reference internal" href="#datetime.tzinfo.utcoffset" title="datetime.tzinfo.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 返回值不为 <code class="docutils literal notranslate"><span class="pre">None</span></code>，则 <a class="reference internal" href="#datetime.tzinfo.dst" title="datetime.tzinfo.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 也不应返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
|
||
<p>默认的 <a class="reference internal" href="#datetime.tzinfo.utcoffset" title="datetime.tzinfo.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 实现会引发 <a class="reference internal" href="exceptions.html#NotImplementedError" title="NotImplementedError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">NotImplementedError</span></code></a>。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>UTC 时差不再限制为一个整数分钟值。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.tzinfo.dst">
|
||
<code class="sig-prename descclassname">tzinfo.</code><code class="sig-name descname">dst</code><span class="sig-paren">(</span><em class="sig-param">dt</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.tzinfo.dst" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>将夏令时（DST）调整返回为一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象，如果 DST 信息未知则返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
|
||
<p>如果 DST 未启用则返回 <code class="docutils literal notranslate"><span class="pre">timedelta(0)</span></code>。 如果 DST 已启用则将差值作为一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象返回（参见 <a class="reference internal" href="#datetime.tzinfo.utcoffset" title="datetime.tzinfo.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 了解详情）。 请注意 DST 差值如果可用，就会直接被加入 <a class="reference internal" href="#datetime.tzinfo.utcoffset" title="datetime.tzinfo.utcoffset"><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code></a> 所返回的 UTC 时差，因此无需额外查询 <a class="reference internal" href="#datetime.tzinfo.dst" title="datetime.tzinfo.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 除非你希望单独获取 DST 信息。 例如，<a class="reference internal" href="#datetime.datetime.timetuple" title="datetime.datetime.timetuple"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.timetuple()</span></code></a> 会调用其 <a class="reference internal" href="#datetime.datetime.tzinfo" title="datetime.datetime.tzinfo"><code class="xref py py-attr docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 属性的 <a class="reference internal" href="#datetime.tzinfo.dst" title="datetime.tzinfo.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 方法来确定应该如何设置 <code class="xref py py-attr docutils literal notranslate"><span class="pre">tm_isdst</span></code> 旗标，而 <a class="reference internal" href="#datetime.tzinfo.fromutc" title="datetime.tzinfo.fromutc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tzinfo.fromutc()</span></code></a> 会调用 <a class="reference internal" href="#datetime.tzinfo.dst" title="datetime.tzinfo.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 来在跨越时区时处理 DST 的改变。</p>
|
||
<p>一个可以同时处理标准时和夏令时的 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类的实例 <em>tz</em> 必须在此情形中保持一致：</p>
|
||
<p><code class="docutils literal notranslate"><span class="pre">tz.utcoffset(dt)</span> <span class="pre">-</span> <span class="pre">tz.dst(dt)</span></code></p>
|
||
<p>必须为具有同样的 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类实例且 <code class="docutils literal notranslate"><span class="pre">dt.tzinfo</span> <span class="pre">==</span> <span class="pre">tz</span></code> 的每个 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象 <em>dt</em> 返回同样的结果，此表达式会产生时区的“标准时差”，它不应取决于具体日期或时间，只取决于地理位置。 <a class="reference internal" href="#datetime.datetime.astimezone" title="datetime.datetime.astimezone"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.astimezone()</span></code></a> 的实现依赖此方法，但无法检测违反规则的情况；确保符合规则是程序员的责任。 如果一个 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类不能保证这一点，也许可以重写 <a class="reference internal" href="#datetime.tzinfo.fromutc" title="datetime.tzinfo.fromutc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tzinfo.fromutc()</span></code></a> 的默认实现以便在任何情况下与 <code class="xref py py-meth docutils literal notranslate"><span class="pre">astimezone()</span></code> 正确配合。</p>
|
||
<p>大多数 <a class="reference internal" href="#datetime.tzinfo.dst" title="datetime.tzinfo.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 的实现可能会如以下两者之一:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">dst</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="c1"># a fixed-offset class: doesn't account for DST</span>
|
||
<span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>或者：</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">dst</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="c1"># Code to set dston and dstoff to the time zone's DST</span>
|
||
<span class="c1"># transition times based on the input dt.year, and expressed</span>
|
||
<span class="c1"># in standard local time.</span>
|
||
|
||
<span class="k">if</span> <span class="n">dston</span> <span class="o"><=</span> <span class="n">dt</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">tzinfo</span><span class="o">=</span><span class="kc">None</span><span class="p">)</span> <span class="o"><</span> <span class="n">dstoff</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">timedelta</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>默认的 <a class="reference internal" href="#datetime.tzinfo.dst" title="datetime.tzinfo.dst"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dst()</span></code></a> 实现会引发 <a class="reference internal" href="exceptions.html#NotImplementedError" title="NotImplementedError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">NotImplementedError</span></code></a>。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>DST 差值不再限制为一个整数分钟值。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.tzinfo.tzname">
|
||
<code class="sig-prename descclassname">tzinfo.</code><code class="sig-name descname">tzname</code><span class="sig-paren">(</span><em class="sig-param">dt</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.tzinfo.tzname" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>将对应于 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象 <em>dt</em> 的时区名称作为字符串返回。 <a class="reference internal" href="#module-datetime" title="datetime: Basic date and time types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code></a> 模块没有定义任何字符串名称相关内容，也不要求名称有任何特定含义。 例如 "GMT", "UTC", "-500", "-5:00", "EDT", "US/Eastern", "America/New York" 都是有效的返回值。 如果字符串名称未知则返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>。 请注意这是一个方法而不是一个固定的字符串，这主要是因为某些 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类可能需要根据所传入的特定 <em>dt</em> 值返回不同的名称，特别是当 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 类要负责处理夏令时的时候。</p>
|
||
<p>默认的 <a class="reference internal" href="#datetime.tzinfo.tzname" title="datetime.tzinfo.tzname"><code class="xref py py-meth docutils literal notranslate"><span class="pre">tzname()</span></code></a> 实现会引发 <a class="reference internal" href="exceptions.html#NotImplementedError" title="NotImplementedError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">NotImplementedError</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<p>这些方法会被 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 或 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象调用，用来与它们的同名方法相对应。 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象会将自身作为传入参数，而 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象会将 <code class="docutils literal notranslate"><span class="pre">None</span></code> 作为传入参数。 这样 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类的方法应当准备好接受 <em>dt</em> 参数值为 <code class="docutils literal notranslate"><span class="pre">None</span></code> 或是 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 类的实例。</p>
|
||
<p>当传入 <code class="docutils literal notranslate"><span class="pre">None</span></code> 时，应当由类的设计者来决定最佳回应方式。 例如，返回 <code class="docutils literal notranslate"><span class="pre">None</span></code> 适用于希望该类提示时间对象不参与 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 协议处理。 让 <code class="docutils literal notranslate"><span class="pre">utcoffset(None)</span></code> 返回标准 UTC 时差也许会更有用处，因为并没有其他可用于发现标准时差的约定惯例。</p>
|
||
<p>当传入一个 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象来回应 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 方法时，<code class="docutils literal notranslate"><span class="pre">dt.tzinfo</span></code> 与 <em>self</em> 是同一对象。 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 方法可以依赖这一点，除非用户代码直接调用了 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 方法。 此行为的目的是使得 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 方法将 <em>dt</em> 解读为本地时间，而不需要担心其他时区的相关对象。</p>
|
||
<p>还有一个额外的 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 方法，某个子类可能会希望重写它：</p>
|
||
<dl class="method">
|
||
<dt id="datetime.tzinfo.fromutc">
|
||
<code class="sig-prename descclassname">tzinfo.</code><code class="sig-name descname">fromutc</code><span class="sig-paren">(</span><em class="sig-param">dt</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.tzinfo.fromutc" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>此方法会由默认的 <a class="reference internal" href="#datetime.datetime.astimezone" title="datetime.datetime.astimezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime.astimezone()</span></code></a> 实现来调用。 当被其调用时，<code class="docutils literal notranslate"><span class="pre">dt.tzinfo</span></code> 为 <em>self</em>，并且 <em>dt</em> 的日期和时间数据会被视为表示 UTC 时间，<a class="reference internal" href="#datetime.tzinfo.fromutc" title="datetime.tzinfo.fromutc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromutc()</span></code></a> 的目标是调整日期和时间数据，返回一个等价的 datetime 来表示 <em>self</em> 的本地时间。</p>
|
||
<p>大多数 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类应该能够毫无问题地继承默认的 <a class="reference internal" href="#datetime.tzinfo.fromutc" title="datetime.tzinfo.fromutc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromutc()</span></code></a> 实现。 它的健壮性足以处理固定差值的时区以及同时负责标准时和夏令时的时区，对于后者甚至还能处理 DST 转换时间在各个年份有变化的情况。 一个默认 <a class="reference internal" href="#datetime.tzinfo.fromutc" title="datetime.tzinfo.fromutc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromutc()</span></code></a> 实现可能无法在所有情况下正确处理的例子是（与 UTC 的）标准时差取决于所经过的特定日期和时间，这种情况可能由于政治原因而出现。 默认的 <code class="xref py py-meth docutils literal notranslate"><span class="pre">astimezone()</span></code> 和 <a class="reference internal" href="#datetime.tzinfo.fromutc" title="datetime.tzinfo.fromutc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromutc()</span></code></a> 实现可能无法生成你希望的结果，如果这个结果恰好是跨越了标准时差发生改变的时刻当中的某个小时值的话。</p>
|
||
<p>忽略针对错误情况的代码，默认 <a class="reference internal" href="#datetime.tzinfo.fromutc" title="datetime.tzinfo.fromutc"><code class="xref py py-meth docutils literal notranslate"><span class="pre">fromutc()</span></code></a> 实现的行为方式如下:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">fromutc</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="c1"># raise ValueError error if dt.tzinfo is not self</span>
|
||
<span class="n">dtoff</span> <span class="o">=</span> <span class="n">dt</span><span class="o">.</span><span class="n">utcoffset</span><span class="p">()</span>
|
||
<span class="n">dtdst</span> <span class="o">=</span> <span class="n">dt</span><span class="o">.</span><span class="n">dst</span><span class="p">()</span>
|
||
<span class="c1"># raise ValueError if dtoff is None or dtdst is None</span>
|
||
<span class="n">delta</span> <span class="o">=</span> <span class="n">dtoff</span> <span class="o">-</span> <span class="n">dtdst</span> <span class="c1"># this is self's standard offset</span>
|
||
<span class="k">if</span> <span class="n">delta</span><span class="p">:</span>
|
||
<span class="n">dt</span> <span class="o">+=</span> <span class="n">delta</span> <span class="c1"># convert to standard local time</span>
|
||
<span class="n">dtdst</span> <span class="o">=</span> <span class="n">dt</span><span class="o">.</span><span class="n">dst</span><span class="p">()</span>
|
||
<span class="c1"># raise ValueError if dtdst is None</span>
|
||
<span class="k">if</span> <span class="n">dtdst</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">dt</span> <span class="o">+</span> <span class="n">dtdst</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">dt</span>
|
||
</pre></div>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<p>在以下 <a class="reference download internal" download="" href="../_downloads/6b45dc135219d1404be49d606589a11d/tzinfo_examples.py"><code class="xref download docutils literal notranslate"><span class="pre">tzinfo_examples.py</span></code></a> 文件中有一些 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 类的例子：</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">tzinfo</span><span class="p">,</span> <span class="n">timedelta</span><span class="p">,</span> <span class="n">datetime</span>
|
||
|
||
<span class="n">ZERO</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="mi">0</span><span class="p">)</span>
|
||
<span class="n">HOUR</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
|
||
<span class="n">SECOND</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">seconds</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
|
||
|
||
<span class="c1"># A class capturing the platform's idea of local time.</span>
|
||
<span class="c1"># (May result in wrong values on historical times in</span>
|
||
<span class="c1"># timezones where UTC offset and/or the DST rules had</span>
|
||
<span class="c1"># changed in the past.)</span>
|
||
<span class="kn">import</span> <span class="nn">time</span> <span class="k">as</span> <span class="nn">_time</span>
|
||
|
||
<span class="n">STDOFFSET</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">seconds</span> <span class="o">=</span> <span class="o">-</span><span class="n">_time</span><span class="o">.</span><span class="n">timezone</span><span class="p">)</span>
|
||
<span class="k">if</span> <span class="n">_time</span><span class="o">.</span><span class="n">daylight</span><span class="p">:</span>
|
||
<span class="n">DSTOFFSET</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">seconds</span> <span class="o">=</span> <span class="o">-</span><span class="n">_time</span><span class="o">.</span><span class="n">altzone</span><span class="p">)</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="n">DSTOFFSET</span> <span class="o">=</span> <span class="n">STDOFFSET</span>
|
||
|
||
<span class="n">DSTDIFF</span> <span class="o">=</span> <span class="n">DSTOFFSET</span> <span class="o">-</span> <span class="n">STDOFFSET</span>
|
||
|
||
<span class="k">class</span> <span class="nc">LocalTimezone</span><span class="p">(</span><span class="n">tzinfo</span><span class="p">):</span>
|
||
|
||
<span class="k">def</span> <span class="nf">fromutc</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">assert</span> <span class="n">dt</span><span class="o">.</span><span class="n">tzinfo</span> <span class="ow">is</span> <span class="bp">self</span>
|
||
<span class="n">stamp</span> <span class="o">=</span> <span class="p">(</span><span class="n">dt</span> <span class="o">-</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1970</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="bp">self</span><span class="p">))</span> <span class="o">//</span> <span class="n">SECOND</span>
|
||
<span class="n">args</span> <span class="o">=</span> <span class="n">_time</span><span class="o">.</span><span class="n">localtime</span><span class="p">(</span><span class="n">stamp</span><span class="p">)[:</span><span class="mi">6</span><span class="p">]</span>
|
||
<span class="n">dst_diff</span> <span class="o">=</span> <span class="n">DSTDIFF</span> <span class="o">//</span> <span class="n">SECOND</span>
|
||
<span class="c1"># Detect fold</span>
|
||
<span class="n">fold</span> <span class="o">=</span> <span class="p">(</span><span class="n">args</span> <span class="o">==</span> <span class="n">_time</span><span class="o">.</span><span class="n">localtime</span><span class="p">(</span><span class="n">stamp</span> <span class="o">-</span> <span class="n">dst_diff</span><span class="p">))</span>
|
||
<span class="k">return</span> <span class="n">datetime</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="n">microsecond</span><span class="o">=</span><span class="n">dt</span><span class="o">.</span><span class="n">microsecond</span><span class="p">,</span>
|
||
<span class="n">tzinfo</span><span class="o">=</span><span class="bp">self</span><span class="p">,</span> <span class="n">fold</span><span class="o">=</span><span class="n">fold</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">utcoffset</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_isdst</span><span class="p">(</span><span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">return</span> <span class="n">DSTOFFSET</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">STDOFFSET</span>
|
||
|
||
<span class="k">def</span> <span class="nf">dst</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_isdst</span><span class="p">(</span><span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">return</span> <span class="n">DSTDIFF</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="n">ZERO</span>
|
||
|
||
<span class="k">def</span> <span class="nf">tzname</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">return</span> <span class="n">_time</span><span class="o">.</span><span class="n">tzname</span><span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">_isdst</span><span class="p">(</span><span class="n">dt</span><span class="p">)]</span>
|
||
|
||
<span class="k">def</span> <span class="nf">_isdst</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="n">tt</span> <span class="o">=</span> <span class="p">(</span><span class="n">dt</span><span class="o">.</span><span class="n">year</span><span class="p">,</span> <span class="n">dt</span><span class="o">.</span><span class="n">month</span><span class="p">,</span> <span class="n">dt</span><span class="o">.</span><span class="n">day</span><span class="p">,</span>
|
||
<span class="n">dt</span><span class="o">.</span><span class="n">hour</span><span class="p">,</span> <span class="n">dt</span><span class="o">.</span><span class="n">minute</span><span class="p">,</span> <span class="n">dt</span><span class="o">.</span><span class="n">second</span><span class="p">,</span>
|
||
<span class="n">dt</span><span class="o">.</span><span class="n">weekday</span><span class="p">(),</span> <span class="mi">0</span><span class="p">,</span> <span class="mi">0</span><span class="p">)</span>
|
||
<span class="n">stamp</span> <span class="o">=</span> <span class="n">_time</span><span class="o">.</span><span class="n">mktime</span><span class="p">(</span><span class="n">tt</span><span class="p">)</span>
|
||
<span class="n">tt</span> <span class="o">=</span> <span class="n">_time</span><span class="o">.</span><span class="n">localtime</span><span class="p">(</span><span class="n">stamp</span><span class="p">)</span>
|
||
<span class="k">return</span> <span class="n">tt</span><span class="o">.</span><span class="n">tm_isdst</span> <span class="o">></span> <span class="mi">0</span>
|
||
|
||
<span class="n">Local</span> <span class="o">=</span> <span class="n">LocalTimezone</span><span class="p">()</span>
|
||
|
||
|
||
<span class="c1"># A complete implementation of current DST rules for major US time zones.</span>
|
||
|
||
<span class="k">def</span> <span class="nf">first_sunday_on_or_after</span><span class="p">(</span><span class="n">dt</span><span class="p">):</span>
|
||
<span class="n">days_to_go</span> <span class="o">=</span> <span class="mi">6</span> <span class="o">-</span> <span class="n">dt</span><span class="o">.</span><span class="n">weekday</span><span class="p">()</span>
|
||
<span class="k">if</span> <span class="n">days_to_go</span><span class="p">:</span>
|
||
<span class="n">dt</span> <span class="o">+=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">days_to_go</span><span class="p">)</span>
|
||
<span class="k">return</span> <span class="n">dt</span>
|
||
|
||
|
||
<span class="c1"># US DST Rules</span>
|
||
<span class="c1">#</span>
|
||
<span class="c1"># This is a simplified (i.e., wrong for a few cases) set of rules for US</span>
|
||
<span class="c1"># DST start and end times. For a complete and up-to-date set of DST rules</span>
|
||
<span class="c1"># and timezone definitions, visit the Olson Database (or try pytz):</span>
|
||
<span class="c1"># http://www.twinsun.com/tz/tz-link.htm</span>
|
||
<span class="c1"># http://sourceforge.net/projects/pytz/ (might not be up-to-date)</span>
|
||
<span class="c1">#</span>
|
||
<span class="c1"># In the US, since 2007, DST starts at 2am (standard time) on the second</span>
|
||
<span class="c1"># Sunday in March, which is the first Sunday on or after Mar 8.</span>
|
||
<span class="n">DSTSTART_2007</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">8</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
|
||
<span class="c1"># and ends at 2am (DST time) on the first Sunday of Nov.</span>
|
||
<span class="n">DSTEND_2007</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">11</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
|
||
<span class="c1"># From 1987 to 2006, DST used to start at 2am (standard time) on the first</span>
|
||
<span class="c1"># Sunday in April and to end at 2am (DST time) on the last</span>
|
||
<span class="c1"># Sunday of October, which is the first Sunday on or after Oct 25.</span>
|
||
<span class="n">DSTSTART_1987_2006</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
|
||
<span class="n">DSTEND_1987_2006</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">10</span><span class="p">,</span> <span class="mi">25</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
|
||
<span class="c1"># From 1967 to 1986, DST used to start at 2am (standard time) on the last</span>
|
||
<span class="c1"># Sunday in April (the one on or after April 24) and to end at 2am (DST time)</span>
|
||
<span class="c1"># on the last Sunday of October, which is the first Sunday</span>
|
||
<span class="c1"># on or after Oct 25.</span>
|
||
<span class="n">DSTSTART_1967_1986</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">24</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
|
||
<span class="n">DSTEND_1967_1986</span> <span class="o">=</span> <span class="n">DSTEND_1987_2006</span>
|
||
|
||
<span class="k">def</span> <span class="nf">us_dst_range</span><span class="p">(</span><span class="n">year</span><span class="p">):</span>
|
||
<span class="c1"># Find start and end times for US DST. For years before 1967, return</span>
|
||
<span class="c1"># start = end for no DST.</span>
|
||
<span class="k">if</span> <span class="mi">2006</span> <span class="o"><</span> <span class="n">year</span><span class="p">:</span>
|
||
<span class="n">dststart</span><span class="p">,</span> <span class="n">dstend</span> <span class="o">=</span> <span class="n">DSTSTART_2007</span><span class="p">,</span> <span class="n">DSTEND_2007</span>
|
||
<span class="k">elif</span> <span class="mi">1986</span> <span class="o"><</span> <span class="n">year</span> <span class="o"><</span> <span class="mi">2007</span><span class="p">:</span>
|
||
<span class="n">dststart</span><span class="p">,</span> <span class="n">dstend</span> <span class="o">=</span> <span class="n">DSTSTART_1987_2006</span><span class="p">,</span> <span class="n">DSTEND_1987_2006</span>
|
||
<span class="k">elif</span> <span class="mi">1966</span> <span class="o"><</span> <span class="n">year</span> <span class="o"><</span> <span class="mi">1987</span><span class="p">:</span>
|
||
<span class="n">dststart</span><span class="p">,</span> <span class="n">dstend</span> <span class="o">=</span> <span class="n">DSTSTART_1967_1986</span><span class="p">,</span> <span class="n">DSTEND_1967_1986</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="p">(</span><span class="n">datetime</span><span class="p">(</span><span class="n">year</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">),</span> <span class="p">)</span> <span class="o">*</span> <span class="mi">2</span>
|
||
|
||
<span class="n">start</span> <span class="o">=</span> <span class="n">first_sunday_on_or_after</span><span class="p">(</span><span class="n">dststart</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">year</span><span class="o">=</span><span class="n">year</span><span class="p">))</span>
|
||
<span class="n">end</span> <span class="o">=</span> <span class="n">first_sunday_on_or_after</span><span class="p">(</span><span class="n">dstend</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">year</span><span class="o">=</span><span class="n">year</span><span class="p">))</span>
|
||
<span class="k">return</span> <span class="n">start</span><span class="p">,</span> <span class="n">end</span>
|
||
|
||
|
||
<span class="k">class</span> <span class="nc">USTimeZone</span><span class="p">(</span><span class="n">tzinfo</span><span class="p">):</span>
|
||
|
||
<span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">hours</span><span class="p">,</span> <span class="n">reprname</span><span class="p">,</span> <span class="n">stdname</span><span class="p">,</span> <span class="n">dstname</span><span class="p">):</span>
|
||
<span class="bp">self</span><span class="o">.</span><span class="n">stdoffset</span> <span class="o">=</span> <span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="n">hours</span><span class="p">)</span>
|
||
<span class="bp">self</span><span class="o">.</span><span class="n">reprname</span> <span class="o">=</span> <span class="n">reprname</span>
|
||
<span class="bp">self</span><span class="o">.</span><span class="n">stdname</span> <span class="o">=</span> <span class="n">stdname</span>
|
||
<span class="bp">self</span><span class="o">.</span><span class="n">dstname</span> <span class="o">=</span> <span class="n">dstname</span>
|
||
|
||
<span class="k">def</span> <span class="fm">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
|
||
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">reprname</span>
|
||
|
||
<span class="k">def</span> <span class="nf">tzname</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">dst</span><span class="p">(</span><span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">dstname</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">stdname</span>
|
||
|
||
<span class="k">def</span> <span class="nf">utcoffset</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">stdoffset</span> <span class="o">+</span> <span class="bp">self</span><span class="o">.</span><span class="n">dst</span><span class="p">(</span><span class="n">dt</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">dst</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">if</span> <span class="n">dt</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">or</span> <span class="n">dt</span><span class="o">.</span><span class="n">tzinfo</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
|
||
<span class="c1"># An exception may be sensible here, in one or both cases.</span>
|
||
<span class="c1"># It depends on how you want to treat them. The default</span>
|
||
<span class="c1"># fromutc() implementation (called by the default astimezone()</span>
|
||
<span class="c1"># implementation) passes a datetime with dt.tzinfo is self.</span>
|
||
<span class="k">return</span> <span class="n">ZERO</span>
|
||
<span class="k">assert</span> <span class="n">dt</span><span class="o">.</span><span class="n">tzinfo</span> <span class="ow">is</span> <span class="bp">self</span>
|
||
<span class="n">start</span><span class="p">,</span> <span class="n">end</span> <span class="o">=</span> <span class="n">us_dst_range</span><span class="p">(</span><span class="n">dt</span><span class="o">.</span><span class="n">year</span><span class="p">)</span>
|
||
<span class="c1"># Can't compare naive to aware objects, so strip the timezone from</span>
|
||
<span class="c1"># dt first.</span>
|
||
<span class="n">dt</span> <span class="o">=</span> <span class="n">dt</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">tzinfo</span><span class="o">=</span><span class="kc">None</span><span class="p">)</span>
|
||
<span class="k">if</span> <span class="n">start</span> <span class="o">+</span> <span class="n">HOUR</span> <span class="o"><=</span> <span class="n">dt</span> <span class="o"><</span> <span class="n">end</span> <span class="o">-</span> <span class="n">HOUR</span><span class="p">:</span>
|
||
<span class="c1"># DST is in effect.</span>
|
||
<span class="k">return</span> <span class="n">HOUR</span>
|
||
<span class="k">if</span> <span class="n">end</span> <span class="o">-</span> <span class="n">HOUR</span> <span class="o"><=</span> <span class="n">dt</span> <span class="o"><</span> <span class="n">end</span><span class="p">:</span>
|
||
<span class="c1"># Fold (an ambiguous hour): use dt.fold to disambiguate.</span>
|
||
<span class="k">return</span> <span class="n">ZERO</span> <span class="k">if</span> <span class="n">dt</span><span class="o">.</span><span class="n">fold</span> <span class="k">else</span> <span class="n">HOUR</span>
|
||
<span class="k">if</span> <span class="n">start</span> <span class="o"><=</span> <span class="n">dt</span> <span class="o"><</span> <span class="n">start</span> <span class="o">+</span> <span class="n">HOUR</span><span class="p">:</span>
|
||
<span class="c1"># Gap (a non-existent hour): reverse the fold rule.</span>
|
||
<span class="k">return</span> <span class="n">HOUR</span> <span class="k">if</span> <span class="n">dt</span><span class="o">.</span><span class="n">fold</span> <span class="k">else</span> <span class="n">ZERO</span>
|
||
<span class="c1"># DST is off.</span>
|
||
<span class="k">return</span> <span class="n">ZERO</span>
|
||
|
||
<span class="k">def</span> <span class="nf">fromutc</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">dt</span><span class="p">):</span>
|
||
<span class="k">assert</span> <span class="n">dt</span><span class="o">.</span><span class="n">tzinfo</span> <span class="ow">is</span> <span class="bp">self</span>
|
||
<span class="n">start</span><span class="p">,</span> <span class="n">end</span> <span class="o">=</span> <span class="n">us_dst_range</span><span class="p">(</span><span class="n">dt</span><span class="o">.</span><span class="n">year</span><span class="p">)</span>
|
||
<span class="n">start</span> <span class="o">=</span> <span class="n">start</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">tzinfo</span><span class="o">=</span><span class="bp">self</span><span class="p">)</span>
|
||
<span class="n">end</span> <span class="o">=</span> <span class="n">end</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">tzinfo</span><span class="o">=</span><span class="bp">self</span><span class="p">)</span>
|
||
<span class="n">std_time</span> <span class="o">=</span> <span class="n">dt</span> <span class="o">+</span> <span class="bp">self</span><span class="o">.</span><span class="n">stdoffset</span>
|
||
<span class="n">dst_time</span> <span class="o">=</span> <span class="n">std_time</span> <span class="o">+</span> <span class="n">HOUR</span>
|
||
<span class="k">if</span> <span class="n">end</span> <span class="o"><=</span> <span class="n">dst_time</span> <span class="o"><</span> <span class="n">end</span> <span class="o">+</span> <span class="n">HOUR</span><span class="p">:</span>
|
||
<span class="c1"># Repeated hour</span>
|
||
<span class="k">return</span> <span class="n">std_time</span><span class="o">.</span><span class="n">replace</span><span class="p">(</span><span class="n">fold</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
|
||
<span class="k">if</span> <span class="n">std_time</span> <span class="o"><</span> <span class="n">start</span> <span class="ow">or</span> <span class="n">dst_time</span> <span class="o">>=</span> <span class="n">end</span><span class="p">:</span>
|
||
<span class="c1"># Standard time</span>
|
||
<span class="k">return</span> <span class="n">std_time</span>
|
||
<span class="k">if</span> <span class="n">start</span> <span class="o"><=</span> <span class="n">std_time</span> <span class="o"><</span> <span class="n">end</span> <span class="o">-</span> <span class="n">HOUR</span><span class="p">:</span>
|
||
<span class="c1"># Daylight saving time</span>
|
||
<span class="k">return</span> <span class="n">dst_time</span>
|
||
|
||
|
||
<span class="n">Eastern</span> <span class="o">=</span> <span class="n">USTimeZone</span><span class="p">(</span><span class="o">-</span><span class="mi">5</span><span class="p">,</span> <span class="s2">"Eastern"</span><span class="p">,</span> <span class="s2">"EST"</span><span class="p">,</span> <span class="s2">"EDT"</span><span class="p">)</span>
|
||
<span class="n">Central</span> <span class="o">=</span> <span class="n">USTimeZone</span><span class="p">(</span><span class="o">-</span><span class="mi">6</span><span class="p">,</span> <span class="s2">"Central"</span><span class="p">,</span> <span class="s2">"CST"</span><span class="p">,</span> <span class="s2">"CDT"</span><span class="p">)</span>
|
||
<span class="n">Mountain</span> <span class="o">=</span> <span class="n">USTimeZone</span><span class="p">(</span><span class="o">-</span><span class="mi">7</span><span class="p">,</span> <span class="s2">"Mountain"</span><span class="p">,</span> <span class="s2">"MST"</span><span class="p">,</span> <span class="s2">"MDT"</span><span class="p">)</span>
|
||
<span class="n">Pacific</span> <span class="o">=</span> <span class="n">USTimeZone</span><span class="p">(</span><span class="o">-</span><span class="mi">8</span><span class="p">,</span> <span class="s2">"Pacific"</span><span class="p">,</span> <span class="s2">"PST"</span><span class="p">,</span> <span class="s2">"PDT"</span><span class="p">)</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>请注意同时负责标准时和夏令时的 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类在每年两次的 DST 转换点上会出现不可避免的微妙问题。具体而言，考虑美国东部时区 (UTC -0500)，它的 EDT 从三月的第二个星期天 1:59 (EST) 之后一分钟开始，并在十一月的第一天星期天 1:59 (EDT) 之后一分钟结束:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span> <span class="n">UTC</span> <span class="mi">3</span><span class="p">:</span><span class="n">MM</span> <span class="mi">4</span><span class="p">:</span><span class="n">MM</span> <span class="mi">5</span><span class="p">:</span><span class="n">MM</span> <span class="mi">6</span><span class="p">:</span><span class="n">MM</span> <span class="mi">7</span><span class="p">:</span><span class="n">MM</span> <span class="mi">8</span><span class="p">:</span><span class="n">MM</span>
|
||
<span class="n">EST</span> <span class="mi">22</span><span class="p">:</span><span class="n">MM</span> <span class="mi">23</span><span class="p">:</span><span class="n">MM</span> <span class="mi">0</span><span class="p">:</span><span class="n">MM</span> <span class="mi">1</span><span class="p">:</span><span class="n">MM</span> <span class="mi">2</span><span class="p">:</span><span class="n">MM</span> <span class="mi">3</span><span class="p">:</span><span class="n">MM</span>
|
||
<span class="n">EDT</span> <span class="mi">23</span><span class="p">:</span><span class="n">MM</span> <span class="mi">0</span><span class="p">:</span><span class="n">MM</span> <span class="mi">1</span><span class="p">:</span><span class="n">MM</span> <span class="mi">2</span><span class="p">:</span><span class="n">MM</span> <span class="mi">3</span><span class="p">:</span><span class="n">MM</span> <span class="mi">4</span><span class="p">:</span><span class="n">MM</span>
|
||
|
||
<span class="n">start</span> <span class="mi">22</span><span class="p">:</span><span class="n">MM</span> <span class="mi">23</span><span class="p">:</span><span class="n">MM</span> <span class="mi">0</span><span class="p">:</span><span class="n">MM</span> <span class="mi">1</span><span class="p">:</span><span class="n">MM</span> <span class="mi">3</span><span class="p">:</span><span class="n">MM</span> <span class="mi">4</span><span class="p">:</span><span class="n">MM</span>
|
||
|
||
<span class="n">end</span> <span class="mi">23</span><span class="p">:</span><span class="n">MM</span> <span class="mi">0</span><span class="p">:</span><span class="n">MM</span> <span class="mi">1</span><span class="p">:</span><span class="n">MM</span> <span class="mi">1</span><span class="p">:</span><span class="n">MM</span> <span class="mi">2</span><span class="p">:</span><span class="n">MM</span> <span class="mi">3</span><span class="p">:</span><span class="n">MM</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>当 DST 开始时（即 "start" 行），本地时钟从 1:59 跳到 3:00。 形式为 2:MM 的时间值在那一天是没有意义的，因此在 DST 开始那一天 <code class="docutils literal notranslate"><span class="pre">astimezone(Eastern)</span></code> 不会输出包含 <code class="docutils literal notranslate"><span class="pre">hour</span> <span class="pre">==</span> <span class="pre">2</span></code> 的结果。 例如，在 2016 年春季时钟向前调整时，我们得到:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">datetime</span><span class="p">,</span> <span class="n">timezone</span>
|
||
<span class="gp">>>> </span><span class="kn">from</span> <span class="nn">tzinfo_examples</span> <span class="kn">import</span> <span class="n">HOUR</span><span class="p">,</span> <span class="n">Eastern</span>
|
||
<span class="gp">>>> </span><span class="n">u0</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">2016</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">13</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="mi">4</span><span class="p">):</span>
|
||
<span class="gp">... </span> <span class="n">u</span> <span class="o">=</span> <span class="n">u0</span> <span class="o">+</span> <span class="n">i</span><span class="o">*</span><span class="n">HOUR</span>
|
||
<span class="gp">... </span> <span class="n">t</span> <span class="o">=</span> <span class="n">u</span><span class="o">.</span><span class="n">astimezone</span><span class="p">(</span><span class="n">Eastern</span><span class="p">)</span>
|
||
<span class="gp">... </span> <span class="nb">print</span><span class="p">(</span><span class="n">u</span><span class="o">.</span><span class="n">time</span><span class="p">(),</span> <span class="s1">'UTC ='</span><span class="p">,</span> <span class="n">t</span><span class="o">.</span><span class="n">time</span><span class="p">(),</span> <span class="n">t</span><span class="o">.</span><span class="n">tzname</span><span class="p">())</span>
|
||
<span class="gp">...</span>
|
||
<span class="go">05:00:00 UTC = 00:00:00 EST</span>
|
||
<span class="go">06:00:00 UTC = 01:00:00 EST</span>
|
||
<span class="go">07:00:00 UTC = 03:00:00 EDT</span>
|
||
<span class="go">08:00:00 UTC = 04:00:00 EDT</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>当 DST 结束时（见 "end" 行），会有更糟糕的潜在问题：本地时间值中有一个小时是不可能没有歧义的：夏令时的最后一小时。 即以北美东部时间表示当天夏令时结束时的形式为 5:MM UTC 的时间。 本地时钟从 1:59 (夏令时) 再次跳回到 1:00 (标准时)。 形式为 1:MM 的本地时间就是有歧义的。 此时 <code class="xref py py-meth docutils literal notranslate"><span class="pre">astimezone()</span></code> 是通过将两个相邻的 UTC 小时映射到两个相同的本地小时来模仿本地时钟的行为。 在这个北美东部时间的示例中，形式为 5:MM 和 6:MM 的 UTC 时间在转换为北美东部时间时都将被映射到 1:MM，但前一个时间会将 <a class="reference internal" href="#datetime.datetime.fold" title="datetime.datetime.fold"><code class="xref py py-attr docutils literal notranslate"><span class="pre">fold</span></code></a> 属性设为 0 而后一个时间会将其设为 1。 例如，在 2016 年秋季时钟往回调整时，我们得到:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">u0</span> <span class="o">=</span> <span class="n">datetime</span><span class="p">(</span><span class="mi">2016</span><span class="p">,</span> <span class="mi">11</span><span class="p">,</span> <span class="mi">6</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="n">timezone</span><span class="o">.</span><span class="n">utc</span><span class="p">)</span>
|
||
<span class="gp">>>> </span><span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="mi">4</span><span class="p">):</span>
|
||
<span class="gp">... </span> <span class="n">u</span> <span class="o">=</span> <span class="n">u0</span> <span class="o">+</span> <span class="n">i</span><span class="o">*</span><span class="n">HOUR</span>
|
||
<span class="gp">... </span> <span class="n">t</span> <span class="o">=</span> <span class="n">u</span><span class="o">.</span><span class="n">astimezone</span><span class="p">(</span><span class="n">Eastern</span><span class="p">)</span>
|
||
<span class="gp">... </span> <span class="nb">print</span><span class="p">(</span><span class="n">u</span><span class="o">.</span><span class="n">time</span><span class="p">(),</span> <span class="s1">'UTC ='</span><span class="p">,</span> <span class="n">t</span><span class="o">.</span><span class="n">time</span><span class="p">(),</span> <span class="n">t</span><span class="o">.</span><span class="n">tzname</span><span class="p">(),</span> <span class="n">t</span><span class="o">.</span><span class="n">fold</span><span class="p">)</span>
|
||
<span class="gp">...</span>
|
||
<span class="go">04:00:00 UTC = 00:00:00 EDT 0</span>
|
||
<span class="go">05:00:00 UTC = 01:00:00 EDT 0</span>
|
||
<span class="go">06:00:00 UTC = 01:00:00 EST 1</span>
|
||
<span class="go">07:00:00 UTC = 02:00:00 EST 0</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>请注意不同的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 实例仅通过 <a class="reference internal" href="#datetime.datetime.fold" title="datetime.datetime.fold"><code class="xref py py-attr docutils literal notranslate"><span class="pre">fold</span></code></a> 属性值来加以区分，它们在比较时会被视为相等。</p>
|
||
<p>不允许时间显示存在歧义的应用需要显式地检查 <a class="reference internal" href="#datetime.datetime.fold" title="datetime.datetime.fold"><code class="xref py py-attr docutils literal notranslate"><span class="pre">fold</span></code></a> 属性的值，或者避免使用混合式的 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类；当使用 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 或者任何其他固定差值的 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 子类例如仅表示 EST（固定差值 -5 小时）或仅表示 EDT（固定差值 -4 小时）的类时是不会有歧义的。</p>
|
||
<div class="admonition seealso">
|
||
<p class="admonition-title">参见</p>
|
||
<dl>
|
||
<dt><a class="reference external" href="https://dateutil.readthedocs.io/en/stable/tz.html">dateutil.tz</a></dt><dd><p><a class="reference internal" href="#module-datetime" title="datetime: Basic date and time types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code></a> 模块有一个基本 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 类（用来处理任意与 UTC 的固定时差）及其 <a class="reference internal" href="#datetime.timezone.utc" title="datetime.timezone.utc"><code class="xref py py-attr docutils literal notranslate"><span class="pre">timezone.utc</span></code></a> 属性（一个 UTC 时区实例）。</p>
|
||
<p><em>dateutil.tz</em> 库将 <em>IANA 时区数据库</em> (又名 Olson 数据库) 引入 Python 并推荐使用。</p>
|
||
</dd>
|
||
<dt><a class="reference external" href="https://www.iana.org/time-zones">IANA 时区数据库</a></dt><dd><p>该时区数据库 (通常称为 tz, tzdata 或 zoneinfo) 包含大量代码和数据用来表示全球许多有代表性的地点的本地时间的历史信息。 它会定期进行更新以反映各政治实体对时区边界、UTC 差值和夏令时规则的更改。</p>
|
||
</dd>
|
||
</dl>
|
||
</div>
|
||
</section>
|
||
<section id="timezone-objects">
|
||
<span id="datetime-timezone"></span><h2><a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 对象<a class="headerlink" href="#timezone-objects" title="永久链接至标题">¶</a></h2>
|
||
<p><a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 类是 <a class="reference internal" href="#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code></a> 的子类，它的每个实例都代表一个以与 UTC 的固定时差来定义的时区。</p>
|
||
<p>此类的对象不可被用于代表某些特殊地点的时区信息，这些地点在一年的不同日期会使用不同的时差，或是在历史上对民用时间进行过调整。</p>
|
||
<dl class="class">
|
||
<dt id="datetime.timezone">
|
||
<em class="property">class </em><code class="sig-prename descclassname">datetime.</code><code class="sig-name descname">timezone</code><span class="sig-paren">(</span><em class="sig-param">offset</em>, <em class="sig-param">name=None</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.timezone" title="永久链接至目标">¶</a></dt>
|
||
<dd><p><em>offset</em> 参数必须指定为一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 对象，表示本地时间与 UTC 的时差。 它必须严格限制于 <code class="docutils literal notranslate"><span class="pre">-timedelta(hours=24)</span></code> 和 <code class="docutils literal notranslate"><span class="pre">timedelta(hours=24)</span></code> 之间，否则会引发 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。</p>
|
||
<p><em>name</em> 参数是可选的。 如果指定则必须为一个字符串，它将被用作 <a class="reference internal" href="#datetime.datetime.tzname" title="datetime.datetime.tzname"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.tzname()</span></code></a> 方法的返回值。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.2 新版功能.</span></p>
|
||
</div>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>UTC 时差不再限制为一个整数分钟值。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.timezone.utcoffset">
|
||
<code class="sig-prename descclassname">timezone.</code><code class="sig-name descname">utcoffset</code><span class="sig-paren">(</span><em class="sig-param">dt</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.timezone.utcoffset" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回当 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 实例被构造时指定的固定值。</p>
|
||
<p><em>dt</em> 参数会被忽略。 返回值是一个 <a class="reference internal" href="#datetime.timedelta" title="datetime.timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code></a> 实例，其值等于本地时间与 UTC 之间的时差。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>UTC 时差不再限制为一个整数分钟值。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.timezone.tzname">
|
||
<code class="sig-prename descclassname">timezone.</code><code class="sig-name descname">tzname</code><span class="sig-paren">(</span><em class="sig-param">dt</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.timezone.tzname" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回当 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 实例被构造时指定的固定值。</p>
|
||
<p>如果没有在构造器中提供 <em>name</em>，则 <code class="docutils literal notranslate"><span class="pre">tzname(dt)</span></code> 所返回的名称将根据 <code class="docutils literal notranslate"><span class="pre">offset</span></code> 值按以下规则生成。 如果 <em>offset</em> 为 <code class="docutils literal notranslate"><span class="pre">timedelta(0)</span></code>，则名称为“UTC”，否则为字符串 <code class="docutils literal notranslate"><span class="pre">UTC±HH:MM</span></code>，其中 ± 为 <code class="docutils literal notranslate"><span class="pre">offset</span></code> 的正负符号，HH 和 MM 分别为表示 <code class="docutils literal notranslate"><span class="pre">offset.hours</span></code> 和 <code class="docutils literal notranslate"><span class="pre">offset.minutes</span></code> 的两个数码。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.6 版更改: </span>由 <code class="docutils literal notranslate"><span class="pre">offset=timedelta(0)</span></code> 生成的名称现在为简单的 <cite>'UTC'</cite> 而不再是 <code class="docutils literal notranslate"><span class="pre">'UTC+00:00'</span></code>。</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.timezone.dst">
|
||
<code class="sig-prename descclassname">timezone.</code><code class="sig-name descname">dst</code><span class="sig-paren">(</span><em class="sig-param">dt</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.timezone.dst" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>总是返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="datetime.timezone.fromutc">
|
||
<code class="sig-prename descclassname">timezone.</code><code class="sig-name descname">fromutc</code><span class="sig-paren">(</span><em class="sig-param">dt</em><span class="sig-paren">)</span><a class="headerlink" href="#datetime.timezone.fromutc" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>返回 <code class="docutils literal notranslate"><span class="pre">dt</span> <span class="pre">+</span> <span class="pre">offset</span></code>。 <em>dt</em> 参数必须为一个感知型 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 实例，其中 <code class="docutils literal notranslate"><span class="pre">tzinfo</span></code> 值设为 <code class="docutils literal notranslate"><span class="pre">self</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<p>类属性：</p>
|
||
<dl class="attribute">
|
||
<dt id="datetime.timezone.utc">
|
||
<code class="sig-prename descclassname">timezone.</code><code class="sig-name descname">utc</code><a class="headerlink" href="#datetime.timezone.utc" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>UTC 时区，<code class="docutils literal notranslate"><span class="pre">timezone(timedelta(0))</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
</section>
|
||
<section id="strftime-and-strptime-behavior">
|
||
<span id="strftime-strptime-behavior"></span><span id="index-0"></span><h2><code class="xref py py-meth docutils literal notranslate"><span class="pre">strftime()</span></code> 和 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 的行为<a class="headerlink" href="#strftime-and-strptime-behavior" title="永久链接至标题">¶</a></h2>
|
||
<p><a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a>, <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 和 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象都支持 <code class="docutils literal notranslate"><span class="pre">strftime(format)</span></code> 方法，可用来创建由一个显式格式字符串所控制的表示时间的字符串。</p>
|
||
<p>相反地，<a class="reference internal" href="#datetime.datetime.strptime" title="datetime.datetime.strptime"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.strptime()</span></code></a> 类会根据表示日期和时间的字符串和相应的格式字符串来创建一个 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象。</p>
|
||
<p>下表提供了 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strftime()</span></code> 与 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 的高层级比较：</p>
|
||
<table class="docutils align-default">
|
||
<colgroup>
|
||
<col style="width: 11%" />
|
||
<col style="width: 37%" />
|
||
<col style="width: 52%" />
|
||
</colgroup>
|
||
<thead>
|
||
<tr class="row-odd"><th class="head"></th>
|
||
<th class="head"><p><code class="docutils literal notranslate"><span class="pre">strftime</span></code></p></th>
|
||
<th class="head"><p><code class="docutils literal notranslate"><span class="pre">strptime</span></code></p></th>
|
||
</tr>
|
||
</thead>
|
||
<tbody>
|
||
<tr class="row-even"><td><p>用法</p></td>
|
||
<td><p>根据给定的格式将对象转换为字符串</p></td>
|
||
<td><p>将字符串解析为给定相应格式的 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p>方法类型</p></td>
|
||
<td><p>实例方法</p></td>
|
||
<td><p>类方法</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p>方法</p></td>
|
||
<td><p><a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a>; <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a>; <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a></p></td>
|
||
<td><p><a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a></p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p>签名</p></td>
|
||
<td><p><code class="docutils literal notranslate"><span class="pre">strftime(format)</span></code></p></td>
|
||
<td><p><code class="docutils literal notranslate"><span class="pre">strptime(date_string,</span> <span class="pre">format)</span></code></p></td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
<section id="strftime-and-strptime-format-codes">
|
||
<h3><code class="xref py py-meth docutils literal notranslate"><span class="pre">strftime()</span></code> 和 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> Format Codes<a class="headerlink" href="#strftime-and-strptime-format-codes" title="永久链接至标题">¶</a></h3>
|
||
<p>以下列表显示了 1989 版 C 标准所要求的全部格式代码，它们在带有标准 C 实现的所有平台上均可用。</p>
|
||
<table class="docutils align-default">
|
||
<colgroup>
|
||
<col style="width: 15%" />
|
||
<col style="width: 43%" />
|
||
<col style="width: 32%" />
|
||
<col style="width: 9%" />
|
||
</colgroup>
|
||
<thead>
|
||
<tr class="row-odd"><th class="head"><p>指令</p></th>
|
||
<th class="head"><p>含意</p></th>
|
||
<th class="head"><p>示例</p></th>
|
||
<th class="head"><p>备注</p></th>
|
||
</tr>
|
||
</thead>
|
||
<tbody>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%a</span></code></p></td>
|
||
<td><p>当地工作日的缩写。</p></td>
|
||
<td><div class="line-block">
|
||
<div class="line">Sun, Mon, ..., Sat
|
||
(en_US);</div>
|
||
<div class="line">So, Mo, ..., Sa
|
||
(de_DE)</div>
|
||
</div>
|
||
</td>
|
||
<td><p>(1)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%A</span></code></p></td>
|
||
<td><p>本地化的星期中每日的完整名称。</p></td>
|
||
<td><div class="line-block">
|
||
<div class="line">Sunday, Monday, ...,
|
||
Saturday (en_US);</div>
|
||
<div class="line">Sonntag, Montag, ...,
|
||
Samstag (de_DE)</div>
|
||
</div>
|
||
</td>
|
||
<td><p>(1)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%w</span></code></p></td>
|
||
<td><p>以十进制数显示的工作日，其中0表示星期日，6表示星期六。</p></td>
|
||
<td><p>0, 1, ..., 6</p></td>
|
||
<td></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%d</span></code></p></td>
|
||
<td><p>补零后，以十进制数显示的月份中的一天。</p></td>
|
||
<td><p>01, 02, ..., 31</p></td>
|
||
<td><p>(9)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%b</span></code></p></td>
|
||
<td><p>当地月份的缩写。</p></td>
|
||
<td><div class="line-block">
|
||
<div class="line">Jan, Feb, ..., Dec
|
||
(en_US);</div>
|
||
<div class="line">Jan, Feb, ..., Dez
|
||
(de_DE)</div>
|
||
</div>
|
||
</td>
|
||
<td><p>(1)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%B</span></code></p></td>
|
||
<td><p>本地化的月份全名。</p></td>
|
||
<td><div class="line-block">
|
||
<div class="line">January, February,
|
||
..., December (en_US);</div>
|
||
<div class="line">Januar, Februar, ...,
|
||
Dezember (de_DE)</div>
|
||
</div>
|
||
</td>
|
||
<td><p>(1)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%m</span></code></p></td>
|
||
<td><p>补零后，以十进制数显示的月份。</p></td>
|
||
<td><p>01, 02, ..., 12</p></td>
|
||
<td><p>(9)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%y</span></code></p></td>
|
||
<td><p>补零后，以十进制数表示的，不带世纪的年份。</p></td>
|
||
<td><p>00, 01, ..., 99</p></td>
|
||
<td><p>(9)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%Y</span></code></p></td>
|
||
<td><p>十进制数表示的带世纪的年份。</p></td>
|
||
<td><p>0001, 0002, ..., 2013,
|
||
2014, ..., 9998, 9999</p></td>
|
||
<td><p>(2)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%H</span></code></p></td>
|
||
<td><p>以补零后的十进制数表示的小时（24 小时制）。</p></td>
|
||
<td><p>00, 01, ..., 23</p></td>
|
||
<td><p>(9)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%I</span></code></p></td>
|
||
<td><p>以补零后的十进制数表示的小时（12 小时制）。</p></td>
|
||
<td><p>01, 02, ..., 12</p></td>
|
||
<td><p>(9)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%p</span></code></p></td>
|
||
<td><p>本地化的 AM 或 PM 。</p></td>
|
||
<td><div class="line-block">
|
||
<div class="line">AM, PM (en_US);</div>
|
||
<div class="line">am, pm (de_DE)</div>
|
||
</div>
|
||
</td>
|
||
<td><p>(1),
|
||
(3)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%M</span></code></p></td>
|
||
<td><p>补零后，以十进制数显示的分钟。</p></td>
|
||
<td><p>00, 01, ..., 59</p></td>
|
||
<td><p>(9)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%S</span></code></p></td>
|
||
<td><p>补零后，以十进制数显示的秒。</p></td>
|
||
<td><p>00, 01, ..., 59</p></td>
|
||
<td><p>(4),
|
||
(9)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%f</span></code></p></td>
|
||
<td><p>以十进制数表示的微秒，在左侧补零。</p></td>
|
||
<td><p>000000, 000001, ...,
|
||
999999</p></td>
|
||
<td><p>(5)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%z</span></code></p></td>
|
||
<td><p>UTC 偏移量，格式为 <code class="docutils literal notranslate"><span class="pre">±HHMM[SS[.ffffff]]</span></code> （如果是简单型对象则为空字符串）。</p></td>
|
||
<td><p>(空), +0000, -0400, +1030, +063415, -030712.345216</p></td>
|
||
<td><p>(6)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%Z</span></code></p></td>
|
||
<td><p>时区名称（如果对象为简单型则为空字符串）。</p></td>
|
||
<td><p>(空), UTC, EST, CST</p></td>
|
||
<td></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%j</span></code></p></td>
|
||
<td><p>以补零后的十进制数表示的一年中的日序号。</p></td>
|
||
<td><p>001, 002, ..., 366</p></td>
|
||
<td><p>(9)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%U</span></code></p></td>
|
||
<td><p>以补零后的十进制数表示的一年中的周序号（星期日作为每周的第一天）。 在新的一年中第一个星期日之前的所有日子都被视为是在第 0 周。</p></td>
|
||
<td><p>00, 01, ..., 53</p></td>
|
||
<td><p>(7),
|
||
(9)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%W</span></code></p></td>
|
||
<td><p>以十进制数表示的一年中的周序号（星期一作为每周的第一天）。 在新的一年中第一个第期一之前的所有日子都被视为是在第 0 周。</p></td>
|
||
<td><p>00, 01, ..., 53</p></td>
|
||
<td><p>(7),
|
||
(9)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%c</span></code></p></td>
|
||
<td><p>本地化的适当日期和时间表示。</p></td>
|
||
<td><div class="line-block">
|
||
<div class="line">Tue Aug 16 21:30:00
|
||
1988 (en_US);</div>
|
||
<div class="line">Di 16 Aug 21:30:00
|
||
1988 (de_DE)</div>
|
||
</div>
|
||
</td>
|
||
<td><p>(1)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%x</span></code></p></td>
|
||
<td><p>本地化的适当日期表示。</p></td>
|
||
<td><div class="line-block">
|
||
<div class="line">08/16/88 (None);</div>
|
||
<div class="line">08/16/1988 (en_US);</div>
|
||
<div class="line">16.08.1988 (de_DE)</div>
|
||
</div>
|
||
</td>
|
||
<td><p>(1)</p></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%X</span></code></p></td>
|
||
<td><p>本地化的适当时间表示。</p></td>
|
||
<td><div class="line-block">
|
||
<div class="line">21:30:00 (en_US);</div>
|
||
<div class="line">21:30:00 (de_DE)</div>
|
||
</div>
|
||
</td>
|
||
<td><p>(1)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%%</span></code></p></td>
|
||
<td><p>字面的 <code class="docutils literal notranslate"><span class="pre">'%'</span></code> 字符。</p></td>
|
||
<td><p>%</p></td>
|
||
<td></td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
<p>为了方便起见，还包括了C89标准不需要的其他一些指示符。 这些参数都对应于 ISO 8601 日期值。</p>
|
||
<table class="docutils align-default">
|
||
<colgroup>
|
||
<col style="width: 15%" />
|
||
<col style="width: 43%" />
|
||
<col style="width: 32%" />
|
||
<col style="width: 9%" />
|
||
</colgroup>
|
||
<thead>
|
||
<tr class="row-odd"><th class="head"><p>指令</p></th>
|
||
<th class="head"><p>含意</p></th>
|
||
<th class="head"><p>示例</p></th>
|
||
<th class="head"><p>备注</p></th>
|
||
</tr>
|
||
</thead>
|
||
<tbody>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%G</span></code></p></td>
|
||
<td><p>带有世纪的 ISO 8601 年份，表示包含大部分 ISO 星期 (<code class="docutils literal notranslate"><span class="pre">%V</span></code>) 的年份。</p></td>
|
||
<td><p>0001, 0002, ..., 2013,
|
||
2014, ..., 9998, 9999</p></td>
|
||
<td><p>(8)</p></td>
|
||
</tr>
|
||
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%u</span></code></p></td>
|
||
<td><p>以十进制数显示的 ISO 8601 星期中的日序号，其中 1 表示星期一。</p></td>
|
||
<td><p>1, 2, ..., 7</p></td>
|
||
<td></td>
|
||
</tr>
|
||
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%V</span></code></p></td>
|
||
<td><p>以十进制数显示的 ISO 8601 星期，以星期一作为每周的第一天。 第 01 周为包含 1 月 4 日的星期。</p></td>
|
||
<td><p>01, 02, ..., 53</p></td>
|
||
<td><p>(8),
|
||
(9)</p></td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
<p>这些代码可能不是在所有平台上都可与 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strftime()</span></code> 方法配合使用。 ISO 8601 年份和 ISO 8601 星期指令并不能与上面的年份和星期序号指令相互替代。 调用 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 时传入不完整或有歧义的 ISO 8601 指令将引发 <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>。</p>
|
||
<p>对完整格式代码集的支持在不同平台上有所差异，因为 Python 要调用所在平台的 C 库的 <code class="xref py py-func docutils literal notranslate"><span class="pre">strftime()</span></code> 函数，而不同平台的差异是很常见的。 要查看你所用平台所支持的完整格式代码集，请参阅 <em class="manpage"><a class="manpage reference external" href="https://manpages.debian.org/strftime(3)">strftime(3)</a></em> 文档。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.6 新版功能: </span>增加了 <code class="docutils literal notranslate"><span class="pre">%G</span></code>, <code class="docutils literal notranslate"><span class="pre">%u</span></code> 和 <code class="docutils literal notranslate"><span class="pre">%V</span></code>。</p>
|
||
</div>
|
||
</section>
|
||
<section id="technical-detail">
|
||
<h3>技术细节<a class="headerlink" href="#technical-detail" title="永久链接至标题">¶</a></h3>
|
||
<p>总体而言，<code class="docutils literal notranslate"><span class="pre">d.strftime(fmt)</span></code> 类似于 <a class="reference internal" href="time.html#module-time" title="time: Time access and conversions."><code class="xref py py-mod docutils literal notranslate"><span class="pre">time</span></code></a> 模块的 <code class="docutils literal notranslate"><span class="pre">time.strftime(fmt,</span> <span class="pre">d.timetuple())</span></code>，但是并非所有对象都支持 <code class="xref py py-meth docutils literal notranslate"><span class="pre">timetuple()</span></code> 方法。</p>
|
||
<p>对于 <a class="reference internal" href="#datetime.datetime.strptime" title="datetime.datetime.strptime"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.strptime()</span></code></a> 类方法，默认值为 <code class="docutils literal notranslate"><span class="pre">1900-01-01T00:00:00.000</span></code>: 任何未在格式字符串中指定的部分都将从默认值中提取。 <a class="footnote-reference brackets" href="#id8" id="id4">4</a></p>
|
||
<p>使用 <code class="docutils literal notranslate"><span class="pre">datetime.strptime(date_string,</span> <span class="pre">format)</span></code> 等价于:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">datetime</span><span class="p">(</span><span class="o">*</span><span class="p">(</span><span class="n">time</span><span class="o">.</span><span class="n">strptime</span><span class="p">(</span><span class="n">date_string</span><span class="p">,</span> <span class="nb">format</span><span class="p">)[</span><span class="mi">0</span><span class="p">:</span><span class="mi">6</span><span class="p">]))</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>除非格式中包含秒以下的部分或时区差值信息，它们在 <code class="docutils literal notranslate"><span class="pre">datetime.strptime</span></code> 中受支持但会被 <code class="docutils literal notranslate"><span class="pre">time.strptime</span></code> 所丢弃。</p>
|
||
<p>对于 <a class="reference internal" href="#datetime.time" title="datetime.time"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象，年、月、日的格式代码不应被使用，因为 <a class="reference internal" href="time.html#module-time" title="time: Time access and conversions."><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a> 对象没有这些值。 如果它们被使用，则年份将被替换为 <code class="docutils literal notranslate"><span class="pre">1900</span></code>，而月和日将被替换为 <code class="docutils literal notranslate"><span class="pre">1</span></code>。</p>
|
||
<p>对于 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象，时、分、秒和微秒的格式代码不应被使用，因为 <a class="reference internal" href="#datetime.date" title="datetime.date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code></a> 对象没有这些值。 如果它们被使用，则它们都将被替换为 <code class="docutils literal notranslate"><span class="pre">0</span></code>。</p>
|
||
<p>出于相同的原因，对于包含当前区域设置字符集所无法表示的 Unicode 码位的格式字符串的处理方式也取决于具体平台。 在某些平台上这样的码位会不加修改地原样输出，而在其他平台上 <code class="docutils literal notranslate"><span class="pre">strftime</span></code> 则可能引发 <a class="reference internal" href="exceptions.html#UnicodeError" title="UnicodeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">UnicodeError</span></code></a> 或只返回一个空字符串。</p>
|
||
<p>注释：</p>
|
||
<ol class="arabic">
|
||
<li><p>由于此格式依赖于当前区域设置，因此对具体输出值应当保持谨慎预期。 字段顺序会发生改变（例如 "month/day/year" 与 "day/month/year"），并且输出可能包含使用区域设置所指定的默认编码格式的 Unicode 字符（例如如果当前区域为 <code class="docutils literal notranslate"><span class="pre">ja_JP</span></code>，则默认编码格式可能为 <code class="docutils literal notranslate"><span class="pre">eucJP</span></code>, <code class="docutils literal notranslate"><span class="pre">SJIS</span></code> 或 <code class="docutils literal notranslate"><span class="pre">utf-8</span></code> 中的一个；使用 <a class="reference internal" href="locale.html#locale.getlocale" title="locale.getlocale"><code class="xref py py-meth docutils literal notranslate"><span class="pre">locale.getlocale()</span></code></a> 可确定当前区域设置的编码格式）。</p></li>
|
||
<li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 方法能够解析整个 [1, 9999] 范围内的年份，但 < 1000 的年份必须加零填充为 4 位数字宽度。</p>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.2 版更改: </span>在之前的版本中，<code class="xref py py-meth docutils literal notranslate"><span class="pre">strftime()</span></code> 方法只限于 >= 1900 的年份。</p>
|
||
</div>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.3 版更改: </span>在版本3.2中，<code class="xref py py-meth docutils literal notranslate"><span class="pre">strftime()</span></code> 方法只限于 years >= 1000。</p>
|
||
</div>
|
||
</li>
|
||
<li><p>当与 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 方法一起使用时，如果使用 <code class="docutils literal notranslate"><span class="pre">%I</span></code> 指令来解析小时，<code class="docutils literal notranslate"><span class="pre">%p</span></code> 指令只影响输出小时字段。</p></li>
|
||
<li><p>与 <a class="reference internal" href="time.html#module-time" title="time: Time access and conversions."><code class="xref py py-mod docutils literal notranslate"><span class="pre">time</span></code></a> 模块不同的是， <a class="reference internal" href="#module-datetime" title="datetime: Basic date and time types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code></a> 模块不支持闰秒。</p></li>
|
||
<li><p>当与 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 方法一起使用时，<code class="docutils literal notranslate"><span class="pre">%f</span></code> 指令可接受一至六个数码及左边的零填充。 <code class="docutils literal notranslate"><span class="pre">%f</span></code> 是对 C 标准中格式字符集的扩展（但单独在 datetime 对象中实现，因此它总是可用）。</p></li>
|
||
<li><p>对于简单型对象，<code class="docutils literal notranslate"><span class="pre">%z</span></code> and <code class="docutils literal notranslate"><span class="pre">%Z</span></code> 格式代码会被替换为空字符串。</p>
|
||
<p>对于一个感知型对象而言：</p>
|
||
<dl class="simple">
|
||
<dt><code class="docutils literal notranslate"><span class="pre">%z</span></code></dt><dd><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code> 会被转换为 <code class="docutils literal notranslate"><span class="pre">±HHMM[SS[.ffffff]]</span></code> 形式的字符串，其中 <code class="docutils literal notranslate"><span class="pre">HH</span></code> 为给出 UTC 时差的小时部分的 2 位数码字符串，<code class="docutils literal notranslate"><span class="pre">MM</span></code> 为给出 UTC 时差的分钟部分的 2 位数码字符串，<code class="docutils literal notranslate"><span class="pre">SS</span></code> 为给出 UTC 时差的秒部分的 2 位数码字符串，而 <code class="docutils literal notranslate"><span class="pre">ffffff</span></code> 为给出 UTC 时差的微秒部分的 6 位数码字符串。 当时差为整数秒时 <code class="docutils literal notranslate"><span class="pre">ffffff</span></code> 部分将被省略，而当时差为整数分钟时 <code class="docutils literal notranslate"><span class="pre">ffffff</span></code> 和 <code class="docutils literal notranslate"><span class="pre">SS</span></code> 部分都将被省略。 例如，如果 <code class="xref py py-meth docutils literal notranslate"><span class="pre">utcoffset()</span></code> 返回 <code class="docutils literal notranslate"><span class="pre">timedelta(hours=-3,</span> <span class="pre">minutes=-30)</span></code>，则 <code class="docutils literal notranslate"><span class="pre">%z</span></code> 会被替换为字符串 <code class="docutils literal notranslate"><span class="pre">'-0330'</span></code>。</p>
|
||
</dd>
|
||
</dl>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>UTC 时差不再限制为一个整数分钟值。</p>
|
||
</div>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.7 版更改: </span>当提供 <code class="docutils literal notranslate"><span class="pre">%z</span></code> 指令给 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 方法时，UTC 差值可以在时、分和秒之间使用冒号分隔符。 例如，<code class="docutils literal notranslate"><span class="pre">'+01:00:00'</span></code> 将被解读为一小时的差值。 此外，提供 <code class="docutils literal notranslate"><span class="pre">'Z'</span></code> 就相当于 <code class="docutils literal notranslate"><span class="pre">'+00:00'</span></code>。</p>
|
||
</div>
|
||
<dl class="simple">
|
||
<dt><code class="docutils literal notranslate"><span class="pre">%Z</span></code></dt><dd><p>如果 <code class="xref py py-meth docutils literal notranslate"><span class="pre">tzname()</span></code> 返回 <code class="docutils literal notranslate"><span class="pre">None</span></code>，<code class="docutils literal notranslate"><span class="pre">%Z</span></code> 会被替换为一个空字符串。 在其他情况下 <code class="docutils literal notranslate"><span class="pre">%Z</span></code> 会被替换为返回值，这必须为一个字符串。</p>
|
||
</dd>
|
||
</dl>
|
||
<div class="versionchanged">
|
||
<p><span class="versionmodified changed">在 3.2 版更改: </span>当提供 <code class="docutils literal notranslate"><span class="pre">%z</span></code> 指令给 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 方法时，将产生一个感知型 <a class="reference internal" href="#datetime.datetime" title="datetime.datetime"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a> 对象。 结果的 <code class="docutils literal notranslate"><span class="pre">tzinfo</span></code> 将被设为一个 <a class="reference internal" href="#datetime.timezone" title="datetime.timezone"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code></a> 实例。</p>
|
||
</div>
|
||
</li>
|
||
<li><p>当与 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 方法一起使用时，<code class="docutils literal notranslate"><span class="pre">%U</span></code> 和 <code class="docutils literal notranslate"><span class="pre">%W</span></code> 仅用于指定星期几和日历年份 (<code class="docutils literal notranslate"><span class="pre">%Y</span></code>) 的计算。</p></li>
|
||
<li><p>类似于 <code class="docutils literal notranslate"><span class="pre">%U</span></code> 和 <code class="docutils literal notranslate"><span class="pre">%W</span></code>，<code class="docutils literal notranslate"><span class="pre">%V</span></code> 仅用于在 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 格式字符串中指定星期几和 ISO 年份 (<code class="docutils literal notranslate"><span class="pre">%G</span></code>) 的计算。 还要注意 <code class="docutils literal notranslate"><span class="pre">%G</span></code> 和 <code class="docutils literal notranslate"><span class="pre">%Y</span></code> 是不可交换的。</p></li>
|
||
<li><p>当于 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 方法一起使用时，前导的零在格式 <code class="docutils literal notranslate"><span class="pre">%d</span></code>, <code class="docutils literal notranslate"><span class="pre">%m</span></code>, <code class="docutils literal notranslate"><span class="pre">%H</span></code>, <code class="docutils literal notranslate"><span class="pre">%I</span></code>, <code class="docutils literal notranslate"><span class="pre">%M</span></code>, <code class="docutils literal notranslate"><span class="pre">%S</span></code>, <code class="docutils literal notranslate"><span class="pre">%J</span></code>, <code class="docutils literal notranslate"><span class="pre">%U</span></code>, <code class="docutils literal notranslate"><span class="pre">%W</span></code> 和 <code class="docutils literal notranslate"><span class="pre">%V</span></code> 中是可选的。 格式 <code class="docutils literal notranslate"><span class="pre">%y</span></code> 不要求有前导的零。</p></li>
|
||
</ol>
|
||
<p class="rubric">备注</p>
|
||
<dl class="footnote brackets">
|
||
<dt class="label" id="id5"><span class="brackets"><a class="fn-backref" href="#id1">1</a></span></dt>
|
||
<dd><p>就是说如果我们忽略相对论效应的话。</p>
|
||
</dd>
|
||
<dt class="label" id="id6"><span class="brackets"><a class="fn-backref" href="#id2">2</a></span></dt>
|
||
<dd><p>这与 Dershowitz 和 Reingold 所著 <em>Calendrical Calculations</em> 中“预期格列高利”历法的定义一致，它是适用于该书中所有运算的基础历法。 请参阅该书了解在预期格利高利历序列与许多其他历法系统之间进行转换的算法。</p>
|
||
</dd>
|
||
<dt class="label" id="id7"><span class="brackets"><a class="fn-backref" href="#id3">3</a></span></dt>
|
||
<dd><p>请参阅 R. H. van Gent 所著 ` ISO 8601 历法的数学指导 <<a class="reference external" href="https://www.staff.science.uu.nl/~gent0113/calendar/isocalendar.htm">https://www.staff.science.uu.nl/~gent0113/calendar/isocalendar.htm</a>>`_ 以获取更完整的说明。</p>
|
||
</dd>
|
||
<dt class="label" id="id8"><span class="brackets"><a class="fn-backref" href="#id4">4</a></span></dt>
|
||
<dd><p>传入 <code class="docutils literal notranslate"><span class="pre">datetime.strptime('Feb</span> <span class="pre">29',</span> <span class="pre">'%b</span> <span class="pre">%d')</span></code> 将导致错误，因为 <code class="docutils literal notranslate"><span class="pre">1900</span></code> 不是闰年。</p>
|
||
</dd>
|
||
</dl>
|
||
</section>
|
||
</section>
|
||
</section>
|
||
|
||
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<div class="sphinxsidebar" role="navigation" aria-label="main navigation">
|
||
<div class="sphinxsidebarwrapper">
|
||
<h3><a href="../contents.html">目录</a></h3>
|
||
<ul>
|
||
<li><a class="reference internal" href="#"><code class="xref py py-mod docutils literal notranslate"><span class="pre">datetime</span></code> --- 基本日期和时间类型</a><ul>
|
||
<li><a class="reference internal" href="#aware-and-naive-objects">感知型对象和简单型对象</a></li>
|
||
<li><a class="reference internal" href="#constants">常量</a></li>
|
||
<li><a class="reference internal" href="#available-types">有效的类型</a><ul>
|
||
<li><a class="reference internal" href="#common-properties">通用的特征属性</a></li>
|
||
<li><a class="reference internal" href="#determining-if-an-object-is-aware-or-naive">确定一个对象是感知型还是简单型</a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#timedelta-objects"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code> 类对象</a><ul>
|
||
<li><a class="reference internal" href="#examples-of-usage-timedelta"><code class="xref py py-class docutils literal notranslate"><span class="pre">timedelta</span></code> 用法示例</a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#date-objects"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code> 对象</a><ul>
|
||
<li><a class="reference internal" href="#examples-of-usage-date"><code class="xref py py-class docutils literal notranslate"><span class="pre">date</span></code> 用法示例</a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#datetime-objects"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code> 对象</a><ul>
|
||
<li><a class="reference internal" href="#examples-of-usage-datetime">用法示例: <code class="xref py py-class docutils literal notranslate"><span class="pre">datetime</span></code></a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#time-objects"><code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code> 对象</a><ul>
|
||
<li><a class="reference internal" href="#examples-of-usage-time">用法示例: <code class="xref py py-class docutils literal notranslate"><span class="pre">time</span></code></a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#tzinfo-objects"><code class="xref py py-class docutils literal notranslate"><span class="pre">tzinfo</span></code> 对象</a></li>
|
||
<li><a class="reference internal" href="#timezone-objects"><code class="xref py py-class docutils literal notranslate"><span class="pre">timezone</span></code> 对象</a></li>
|
||
<li><a class="reference internal" href="#strftime-and-strptime-behavior"><code class="xref py py-meth docutils literal notranslate"><span class="pre">strftime()</span></code> 和 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> 的行为</a><ul>
|
||
<li><a class="reference internal" href="#strftime-and-strptime-format-codes"><code class="xref py py-meth docutils literal notranslate"><span class="pre">strftime()</span></code> 和 <code class="xref py py-meth docutils literal notranslate"><span class="pre">strptime()</span></code> Format Codes</a></li>
|
||
<li><a class="reference internal" href="#technical-detail">技术细节</a></li>
|
||
</ul>
|
||
</li>
|
||
</ul>
|
||
</li>
|
||
</ul>
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<p class="topless"><a href="calendar.html"
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title="下一章"><code class="xref py py-mod docutils literal notranslate"><span class="pre">calendar</span></code> --- 日历相关函数</a></p>
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