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<section id="dictionary-objects">
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<span id="dictobjects"></span><h1>字典对象<a class="headerlink" href="#dictionary-objects" title="永久链接至标题">¶</a></h1>
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<span class="target" id="index-0"></span><dl class="type">
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<dt id="c.PyDictObject">
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<code class="sig-name descname">PyDictObject</code><a class="headerlink" href="#c.PyDictObject" title="永久链接至目标">¶</a></dt>
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<dd><p>这个 <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject</span></code></a> 的子类型代表一个Python字典对象。</p>
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</dd></dl>
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<dl class="var">
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<dt id="c.PyDict_Type">
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<a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a> <code class="sig-name descname">PyDict_Type</code><a class="headerlink" href="#c.PyDict_Type" title="永久链接至目标">¶</a></dt>
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<dd><p>Python字典类型表示为 <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyTypeObject</span></code></a> 的实例。这与Python层面的 <a class="reference internal" href="../library/stdtypes.html#dict" title="dict"><code class="xref py py-class docutils literal notranslate"><span class="pre">dict</span></code></a> 是相同的对象。</p>
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</dd></dl>
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<dl class="function">
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<dt id="c.PyDict_Check">
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int <code class="sig-name descname">PyDict_Check</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Check" title="永久链接至目标">¶</a></dt>
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<dd><p>如果 <em>p</em> 是字典对象或者字典类型的子类型的实例，则返回真。</p>
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</dd></dl>
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<dl class="function">
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<dt id="c.PyDict_CheckExact">
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int <code class="sig-name descname">PyDict_CheckExact</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_CheckExact" title="永久链接至目标">¶</a></dt>
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<dd><p>如果 <em>p</em> 是字典对象但不是字典类型的子类型的实例，则返回真。</p>
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</dd></dl>
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<dl class="function">
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<dt id="c.PyDict_New">
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<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_New</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_New" title="永久链接至目标">¶</a></dt>
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<dd><em class="refcount">Return value: New reference.</em><p>返回一个新的空字典，失败时返回 <code class="docutils literal notranslate"><span class="pre">NULL</span></code>。</p>
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</dd></dl>
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<dl class="function">
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<dt id="c.PyDictProxy_New">
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<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDictProxy_New</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *mapping</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDictProxy_New" title="永久链接至目标">¶</a></dt>
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<dd><em class="refcount">Return value: New reference.</em><p>返回 <a class="reference internal" href="../library/types.html#types.MappingProxyType" title="types.MappingProxyType"><code class="xref py py-class docutils literal notranslate"><span class="pre">types.MappingProxyType</span></code></a> 对象，用于强制执行只读行为的映射。这通常用于创建视图以防止修改非动态类类型的字典。</p>
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</dd></dl>
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<dl class="function">
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<dt id="c.PyDict_Clear">
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void <code class="sig-name descname">PyDict_Clear</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Clear" title="永久链接至目标">¶</a></dt>
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<dd><p>清空现有字典的所有键值对。</p>
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</dd></dl>
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<dl class="function">
|
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<dt id="c.PyDict_Contains">
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int <code class="sig-name descname">PyDict_Contains</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Contains" title="永久链接至目标">¶</a></dt>
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<dd><p>确定 <em>key</em> 是否包含在字典 <em>p</em> 中。如果 <em>key</em> 匹配上 <em>p</em> 的某一项，则返回 <code class="docutils literal notranslate"><span class="pre">1</span></code> ，否则返回 <code class="docutils literal notranslate"><span class="pre">0</span></code> 。返回 <code class="docutils literal notranslate"><span class="pre">-1</span></code> 表示出错。这等同于Python表达式 <code class="docutils literal notranslate"><span class="pre">key</span> <span class="pre">in</span> <span class="pre">p</span></code> 。</p>
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</dd></dl>
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|
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<dl class="function">
|
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<dt id="c.PyDict_Copy">
|
||
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_Copy</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Copy" title="永久链接至目标">¶</a></dt>
|
||
<dd><em class="refcount">Return value: New reference.</em><p>返回与 <em>p</em> 包含相同键值对的新字典。</p>
|
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</dd></dl>
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|
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<dl class="function">
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<dt id="c.PyDict_SetItem">
|
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int <code class="sig-name descname">PyDict_SetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *key</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *val</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_SetItem" title="永久链接至目标">¶</a></dt>
|
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<dd><p>使用 <em>key</em> 作为键将 <em>val</em> 插入字典 <em>p</em>。 <em>key</em> 必须为 <a class="reference internal" href="../glossary.html#term-hashable"><span class="xref std std-term">hashable</span></a>；如果不是，则将引发 <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>。 成功时返回 <code class="docutils literal notranslate"><span class="pre">0</span></code>，失败时返回 <code class="docutils literal notranslate"><span class="pre">-1</span></code>。 此函数 <em>不会</em> 附带对 <em>val</em> 的引用。</p>
|
||
</dd></dl>
|
||
|
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<dl class="function">
|
||
<dt id="c.PyDict_SetItemString">
|
||
int <code class="sig-name descname">PyDict_SetItemString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, const char<em> *key</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *val</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_SetItemString" title="永久链接至目标">¶</a></dt>
|
||
<dd><p id="index-1">使用 <em>key</em> 作为键将 <em>val</em> 插入到字典 <em>p</em>。 <em>key</em> 应当为 <code class="xref c c-type docutils literal notranslate"><span class="pre">const</span> <span class="pre">char*</span></code>。 键对象是使用 <code class="docutils literal notranslate"><span class="pre">PyUnicode_FromString(key)</span></code> 创建的。 成功时返回 <code class="docutils literal notranslate"><span class="pre">0</span></code>，失败时返回 <code class="docutils literal notranslate"><span class="pre">-1</span></code>。 此函数 <em>不会</em> 附带对 <em>val</em> 的引用。</p>
|
||
</dd></dl>
|
||
|
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<dl class="function">
|
||
<dt id="c.PyDict_DelItem">
|
||
int <code class="sig-name descname">PyDict_DelItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_DelItem" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>移除字典 <em>p</em> 中键为 <em>key</em> 的条目。 <em>key</em> 必须是可哈希的；如果不是，则会引发 <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>。 如果字典中没有 <em>key</em>，则会引发 <a class="reference internal" href="../library/exceptions.html#KeyError" title="KeyError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">KeyError</span></code></a>。 成功时返回 <code class="docutils literal notranslate"><span class="pre">0</span></code>，失败时返回 <code class="docutils literal notranslate"><span class="pre">-1</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_DelItemString">
|
||
int <code class="sig-name descname">PyDict_DelItemString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, const char<em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_DelItemString" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>移除字典 <em>p</em> 中由字符串 <em>key</em> 指定的键的条目。 如果字典中没有 <em>key</em>，则会引发 <a class="reference internal" href="../library/exceptions.html#KeyError" title="KeyError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">KeyError</span></code></a>。 成功时返回 <code class="docutils literal notranslate"><span class="pre">0</span></code>，失败时返回 <code class="docutils literal notranslate"><span class="pre">-1</span></code>。</p>
|
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</dd></dl>
|
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<dl class="function">
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<dt id="c.PyDict_GetItem">
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<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_GetItem</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_GetItem" title="永久链接至目标">¶</a></dt>
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<dd><em class="refcount">Return value: Borrowed reference.</em><p>从字典 <em>p</em> 中返回以 <em>key</em> 为键的对象。 如果键名 <em>key</em> 不存在但 <em>没有</em> 设置一个异常则返回 <code class="docutils literal notranslate"><span class="pre">NULL</span></code>。</p>
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||
<p>需要注意的是，调用 <a class="reference internal" href="../reference/datamodel.html#object.__hash__" title="object.__hash__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__hash__()</span></code></a> 和 <a class="reference internal" href="../reference/datamodel.html#object.__eq__" title="object.__eq__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__eq__()</span></code></a> 方法产生的异常不会被抛出。改用 <a class="reference internal" href="#c.PyDict_GetItemWithError" title="PyDict_GetItemWithError"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_GetItemWithError()</span></code></a> 获得错误报告。</p>
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</dd></dl>
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|
||
<dl class="function">
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<dt id="c.PyDict_GetItemWithError">
|
||
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_GetItemWithError</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_GetItemWithError" title="永久链接至目标">¶</a></dt>
|
||
<dd><em class="refcount">Return value: Borrowed reference.</em><p><a class="reference internal" href="#c.PyDict_GetItem" title="PyDict_GetItem"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_GetItem()</span></code></a> 的变种，它不会屏蔽异常。 当异常发生时将返回 <code class="docutils literal notranslate"><span class="pre">NULL</span></code> <strong>并且</strong> 设置一个异常。 如果键不存在则返回 <code class="docutils literal notranslate"><span class="pre">NULL</span></code> <strong>并且不会</strong> 设置一个异常。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_GetItemString">
|
||
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_GetItemString</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, const char<em> *key</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_GetItemString" title="永久链接至目标">¶</a></dt>
|
||
<dd><em class="refcount">Return value: Borrowed reference.</em><p>这与 <a class="reference internal" href="#c.PyDict_GetItem" title="PyDict_GetItem"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_GetItem()</span></code></a> 一样，但是 <em>key</em> 被指定为 <code class="xref c c-type docutils literal notranslate"><span class="pre">const</span> <span class="pre">char*</span></code>，而不是 <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject*</span></code></a>。</p>
|
||
<p>需要注意的是，调用 <a class="reference internal" href="../reference/datamodel.html#object.__hash__" title="object.__hash__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__hash__()</span></code></a> 、 <a class="reference internal" href="../reference/datamodel.html#object.__eq__" title="object.__eq__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__eq__()</span></code></a> 方法和创建一个临时的字符串对象时产生的异常不会被抛出。改用 <a class="reference internal" href="#c.PyDict_GetItemWithError" title="PyDict_GetItemWithError"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_GetItemWithError()</span></code></a> 获得错误报告。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_SetDefault">
|
||
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_SetDefault</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *key</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *defaultobj</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_SetDefault" title="永久链接至目标">¶</a></dt>
|
||
<dd><em class="refcount">Return value: Borrowed reference.</em><p>这跟Python层面的 <a class="reference internal" href="../library/stdtypes.html#dict.setdefault" title="dict.setdefault"><code class="xref py py-meth docutils literal notranslate"><span class="pre">dict.setdefault()</span></code></a> 一样。如果键 <em>key</em> 存在，它返回在字典 <em>p</em> 里面对应的值。如果键不存在，它会和值 <em>defaultobj</em> 一起插入并返回 <em>defaultobj</em> 。这个函数只计算 <em>key</em> 的哈希函数一次，而不是在查找和插入时分别计算它。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.4 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_Items">
|
||
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_Items</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Items" title="永久链接至目标">¶</a></dt>
|
||
<dd><em class="refcount">Return value: New reference.</em><p>返回一个包含字典中所有键值项的 <a class="reference internal" href="list.html#c.PyListObject" title="PyListObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyListObject</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_Keys">
|
||
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_Keys</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Keys" title="永久链接至目标">¶</a></dt>
|
||
<dd><em class="refcount">Return value: New reference.</em><p>返回一个包含字典中所有键(keys)的 <a class="reference internal" href="list.html#c.PyListObject" title="PyListObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyListObject</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_Values">
|
||
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyDict_Values</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Values" title="永久链接至目标">¶</a></dt>
|
||
<dd><em class="refcount">Return value: New reference.</em><p>返回一个包含字典中所有值(values)的 <a class="reference internal" href="list.html#c.PyListObject" title="PyListObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyListObject</span></code></a>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_Size">
|
||
Py_ssize_t <code class="sig-name descname">PyDict_Size</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Size" title="永久链接至目标">¶</a></dt>
|
||
<dd><p id="index-2">返回字典中项目数，等价于对字典 <em>p</em> 使用 <code class="docutils literal notranslate"><span class="pre">len(p)</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_Next">
|
||
int <code class="sig-name descname">PyDict_Next</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *p</em>, Py_ssize_t<em> *ppos</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> **pkey</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> **pvalue</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Next" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>迭代字典 <em>p</em> 中的所有键值对。 在第一次调用此函数开始迭代之前，由 <em>ppos</em> 所引用的 <code class="xref c c-type docutils literal notranslate"><span class="pre">Py_ssize_t</span></code> 必须被初始化为 <code class="docutils literal notranslate"><span class="pre">0</span></code>；该函数将为字典中的每个键值对返回真值，一旦所有键值对都报告完毕则返回假值。 形参 <em>pkey</em> 和 <em>pvalue</em> 应当指向 <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject*</span></code></a> 变量，它们将分别使用每个键和值来填充，或者也可以为 <code class="docutils literal notranslate"><span class="pre">NULL</span></code>。 通过它们返回的任何引用都是暂借的。 <em>ppos</em> 在迭代期间不应被更改。 它的值表示内部字典结构中的偏移量，并且由于结构是稀疏的，因此偏移量并不连续。</p>
|
||
<p>例如</p>
|
||
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="n">PyObject</span><span class="w"> </span><span class="o">*</span><span class="n">key</span><span class="p">,</span><span class="w"> </span><span class="o">*</span><span class="n">value</span><span class="p">;</span>
|
||
<span class="n">Py_ssize_t</span><span class="w"> </span><span class="n">pos</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
||
|
||
<span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="n">PyDict_Next</span><span class="p">(</span><span class="n">self</span><span class="o">-></span><span class="n">dict</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">pos</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">key</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">value</span><span class="p">))</span><span class="w"> </span><span class="p">{</span>
|
||
<span class="w"> </span><span class="cm">/* do something interesting with the values... */</span>
|
||
<span class="w"> </span><span class="p">...</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>字典 <em>p</em> 不应该在遍历期间发生改变。在遍历字典时，改变键中的值是安全的，但仅限于键的集合不发生改变。例如:</p>
|
||
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="n">PyObject</span><span class="w"> </span><span class="o">*</span><span class="n">key</span><span class="p">,</span><span class="w"> </span><span class="o">*</span><span class="n">value</span><span class="p">;</span>
|
||
<span class="n">Py_ssize_t</span><span class="w"> </span><span class="n">pos</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
||
|
||
<span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="n">PyDict_Next</span><span class="p">(</span><span class="n">self</span><span class="o">-></span><span class="n">dict</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">pos</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">key</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">value</span><span class="p">))</span><span class="w"> </span><span class="p">{</span>
|
||
<span class="w"> </span><span class="kt">long</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">PyLong_AsLong</span><span class="p">(</span><span class="n">value</span><span class="p">);</span>
|
||
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">i</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="mi">-1</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="n">PyErr_Occurred</span><span class="p">())</span><span class="w"> </span><span class="p">{</span>
|
||
<span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="mi">-1</span><span class="p">;</span>
|
||
<span class="w"> </span><span class="p">}</span>
|
||
<span class="w"> </span><span class="n">PyObject</span><span class="w"> </span><span class="o">*</span><span class="n">o</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">PyLong_FromLong</span><span class="p">(</span><span class="n">i</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">1</span><span class="p">);</span>
|
||
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">o</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="nb">NULL</span><span class="p">)</span>
|
||
<span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="mi">-1</span><span class="p">;</span>
|
||
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">PyDict_SetItem</span><span class="p">(</span><span class="n">self</span><span class="o">-></span><span class="n">dict</span><span class="p">,</span><span class="w"> </span><span class="n">key</span><span class="p">,</span><span class="w"> </span><span class="n">o</span><span class="p">)</span><span class="w"> </span><span class="o"><</span><span class="w"> </span><span class="mi">0</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||
<span class="w"> </span><span class="n">Py_DECREF</span><span class="p">(</span><span class="n">o</span><span class="p">);</span>
|
||
<span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="mi">-1</span><span class="p">;</span>
|
||
<span class="w"> </span><span class="p">}</span>
|
||
<span class="w"> </span><span class="n">Py_DECREF</span><span class="p">(</span><span class="n">o</span><span class="p">);</span>
|
||
<span class="p">}</span>
|
||
</pre></div>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_Merge">
|
||
int <code class="sig-name descname">PyDict_Merge</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *a</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *b</em>, int<em> override</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Merge" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>对映射对象 <em>b</em> 进行迭代，将键值对添加到字典 <em>a</em>。 <em>b</em> 可以是一个字典，或任何支持 <a class="reference internal" href="mapping.html#c.PyMapping_Keys" title="PyMapping_Keys"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMapping_Keys()</span></code></a> 和 <a class="reference internal" href="object.html#c.PyObject_GetItem" title="PyObject_GetItem"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_GetItem()</span></code></a> 的对象。 如果 <em>override</em> 为真值，则如果在 <em>b</em> 中找到相同的键则 <em>a</em> 中已存在的相应键值对将被替换，否则如果在 <em>a</em> 中没有相同的键则只是添加键值对。 当成功时返回 <code class="docutils literal notranslate"><span class="pre">0</span></code> 或者当引发异常时返回 <code class="docutils literal notranslate"><span class="pre">-1</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_Update">
|
||
int <code class="sig-name descname">PyDict_Update</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *a</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *b</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_Update" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>这与 C 中的 <code class="docutils literal notranslate"><span class="pre">PyDict_Merge(a,</span> <span class="pre">b,</span> <span class="pre">1)</span></code> 一样，也类似于 Python 中的 <code class="docutils literal notranslate"><span class="pre">a.update(b)</span></code>，差别在于 <a class="reference internal" href="#c.PyDict_Update" title="PyDict_Update"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyDict_Update()</span></code></a> 在第二个参数没有 "keys" 属性时不会回退到迭代键值对的序列。 当成功时返回 <code class="docutils literal notranslate"><span class="pre">0</span></code> 或者当引发异常时返回 <code class="docutils literal notranslate"><span class="pre">-1</span></code>。</p>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_MergeFromSeq2">
|
||
int <code class="sig-name descname">PyDict_MergeFromSeq2</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *a</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *seq2</em>, int<em> override</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_MergeFromSeq2" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>将 <em>seq2</em> 中的键值对更新或合并到字典 <em>a</em>。 <em>seq2</em> 必须为产生长度为 2 的用作键值对的元素的可迭代对象。 当存在重复的键时，如果 <em>override</em> 真值则最后出现的键胜出。 当成功时返回 <code class="docutils literal notranslate"><span class="pre">0</span></code> 或者当引发异常时返回 <code class="docutils literal notranslate"><span class="pre">-1</span></code>。 等价的 Python 代码（返回值除外）:</p>
|
||
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="n">def</span><span class="w"> </span><span class="n">PyDict_MergeFromSeq2</span><span class="p">(</span><span class="n">a</span><span class="p">,</span><span class="w"> </span><span class="n">seq2</span><span class="p">,</span><span class="w"> </span><span class="n">override</span><span class="p">)</span><span class="o">:</span>
|
||
<span class="w"> </span><span class="k">for</span><span class="w"> </span><span class="n">key</span><span class="p">,</span><span class="w"> </span><span class="n">value</span><span class="w"> </span><span class="n">in</span><span class="w"> </span><span class="n">seq2</span><span class="o">:</span>
|
||
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="n">override</span><span class="w"> </span><span class="n">or</span><span class="w"> </span><span class="n">key</span><span class="w"> </span><span class="n">not</span><span class="w"> </span><span class="n">in</span><span class="w"> </span><span class="n">a</span><span class="o">:</span>
|
||
<span class="w"> </span><span class="n">a</span><span class="p">[</span><span class="n">key</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">value</span>
|
||
</pre></div>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="function">
|
||
<dt id="c.PyDict_ClearFreeList">
|
||
int <code class="sig-name descname">PyDict_ClearFreeList</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDict_ClearFreeList" title="永久链接至目标">¶</a></dt>
|
||
<dd><p>清空释放列表。 返回所释放的条目数。</p>
|
||
<div class="versionadded">
|
||
<p><span class="versionmodified added">3.3 新版功能.</span></p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
</section>
|
||
|
||
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<div class="sphinxsidebar" role="navigation" aria-label="main navigation">
|
||
<div class="sphinxsidebarwrapper">
|
||
<h4>上一个主题</h4>
|
||
<p class="topless"><a href="list.html"
|
||
title="上一章">列表对象</a></p>
|
||
<h4>下一个主题</h4>
|
||
<p class="topless"><a href="set.html"
|
||
title="下一章">集合对象</a></p>
|
||
<div role="note" aria-label="source link">
|
||
<h3>本页</h3>
|
||
<ul class="this-page-menu">
|
||
<li><a href="../bugs.html">报告 Bug</a></li>
|
||
<li>
|
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