367 lines
28 KiB
HTML
367 lines
28 KiB
HTML
<!DOCTYPE html>
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<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
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<head><meta http-equiv="x-ua-compatible" content="ie=edge">
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
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<title>赋值运算符</title>
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<link rel="stylesheet" href="ext.css" />
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<link rel="stylesheet" href="site_modules.css" />
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</head>
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<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-c_language_operator_assignment skin-cppreference2 action-view cpp-navbar">
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<div id="cpp-content-base">
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<div id="content"><a id="top"></a>
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<h1 id="firstHeading" class="firstHeading">赋值运算符</h1>
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<div id="bodyContent">
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<div id="contentSub"><span class="subpages">< <a href="c.html">c</a>‎ | <a href="c-language.html">language</a></span></div>
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<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
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<p>赋值及复合赋值运算符是二元运算符，它们用在其右侧的值修改在其左侧的变量。</p>
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<table class="wikitable" style="font-size:85%;">
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<tr style="text-align:center">
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<th>运算符</th>
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<th>运算符名</th>
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<th>示例</th>
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<th>描述</th>
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<th>等价</th>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy1">=</span></span></span></td>
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<td>基本赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>b</b></td>
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<td style="background: #ececec; color: grey; vertical-align: middle; text-align: center;" class="table-na"><small>N/A</small></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">+</span><span class="sy1">=</span></span></span></td>
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<td>加法赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy2">+</span><span class="sy1">=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>a</b> 与 <b>b</b> 的和</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy2">+</span> b</span></span></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">-</span><span class="sy1">=</span></span></span></td>
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<td>减法赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy2">-</span><span class="sy1">=</span> b</span></span></td>
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<td><b>a</b> 变得等于从 <b>a</b> 减 <b>b</b> 的差</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy2">-</span> b</span></span></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">*</span><span class="sy1">=</span></span></span></td>
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<td>乘法赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy2">*</span><span class="sy1">=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>a</b> 与 <b>b</b> 的积</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy2">*</span> b</span></span></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">/</span><span class="sy1">=</span></span></span></td>
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<td>除法赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy2">/</span><span class="sy1">=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>a</b> 除以 <b>b</b>的商</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy2">/</span> b</span></span></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">%</span><span class="sy1">=</span></span></span></td>
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<td>模赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy2">%</span><span class="sy1">=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>a</b> 除以 <b>b</b> 的余数</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy2">%</span> b</span></span></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy3">&</span><span class="sy1">=</span></span></span></td>
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<td>逐位与赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy3">&</span><span class="sy1">=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>a</b> 与 <b>b</b> 的逐位或</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy3">&</span> b</span></span></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy3">|</span><span class="sy1">=</span></span></span></td>
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<td>逐位或赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy3">|</span><span class="sy1">=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>a</b> 与 <b>b</b> 的逐位与</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy3">|</span> b</span></span></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy3">^</span><span class="sy1">=</span></span></span></td>
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<td>逐位异或赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy3">^</span><span class="sy1">=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>a</b> 与 <b>b</b> 的逐位异或</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy3">^</span> b</span></span></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy1"><<=</span></span></span></td>
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<td>逐位左移赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1"><<=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>a</b> 左移 <b>b</b> 位</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy1"><<</span> b</span></span></td>
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</tr>
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<tr style="text-align:center">
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<td><span class="t-c"><span class="mw-geshi c source-c"><span class="sy1">>>=</span></span></span></td>
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<td>逐位右移赋值</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">>>=</span> b</span></span></td>
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<td><b>a</b> 变得等于 <b>a</b> 右移 <b>b</b> 位</td>
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<td><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> a <span class="sy1">>></span> b</span></span></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E7.AE.80.E5.8D.95.E8.B5.8B.E5.80.BC">简单赋值</span></h3>
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<p>简单赋值运算符表达式拥有形式</p>
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<table class="t-sdsc-begin">
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<tr>
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<td colspan="10" class="t-sdsc-sep"></td>
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</tr>
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<tr class="t-sdsc">
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<td class="t-sdsc-nopad"><span class="t-spar">lhs</span> <code><b>=</b></code> <span class="t-spar">rhs</span></td>
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<td class="t-sdsc-nopad"></td>
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<td class="t-sdsc-nopad"></td>
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</tr>
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<tr>
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<td colspan="10" class="t-sdsc-sep"></td>
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</tr>
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</table>
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<p>其中</p>
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<table class="t-par-begin">
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<tr class="t-par">
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<td><span class="t-spar">lhs</span></td>
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<td>-</td>
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<td>任何完整对象类型的<a href="c-language-value_category.html">可修改左值</a>表达式</td>
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</tr>
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<tr class="t-par">
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<td><span class="t-spar">rhs</span></td>
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<td>-</td>
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<td>任何<a href="c-language-conversion.html">可隐式转换</a>成 <span class="t-spar">lhs</span> 或与 <span class="t-spar">lhs</span> <a href="c-language-types.html#.E5.85.BC.E5.AE.B9.E7.B1.BB.E5.9E.8B">兼容</a>类型的表达式</td>
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</tr>
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</table>
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<p>赋值进行从 <span class="t-spar">rhs</span> 的值到 <span class="t-spar">lhs</span> 类型的<a href="c-language-conversion.html">隐式转换</a>，然后用 <span class="t-spar">rhs</span> 转换后的值替换 <span class="t-spar">lhs</span> 所指代对象中的值。</p>
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<p>赋值亦返回存储于 <code>lhs</code> 中的相同值（故如 <span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> b <span class="sy1">=</span> c</span></span> 的表达式是可行的）。赋值运算符的<a href="c-language-value_category.html">值类别</a>是非左值（故如 <span class="t-c"><span class="mw-geshi c source-c"><span class="br0">(</span>a<span class="sy1">=</span>b<span class="br0">)</span><span class="sy1">=</span>c</span></span> 的表达式非法）。</p>
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<p><span class="t-spar">rhs</span> 与 <span class="t-spar">lhs</span> 必须满足下列条件之一：</p>
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<ul>
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<li><span class="t-spar">lhs</span> 与 <span class="t-spar">rhs</span> 拥有<a href="c-language-types.html#.E5.85.BC.E5.AE.B9.E7.B1.BB.E5.9E.8B">兼容</a>的 <a href="c-language-struct.html">struct</a> 或 <a href="c-language-union.html">union</a> 类型，或……</li>
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<li><span class="t-spar">rhs</span> 必须<a href="c-language-conversion.html">可隐式转换</a>成 <span class="t-spar">lhs</span> ，这表示</li>
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</ul>
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<dl>
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<dd>
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<ul>
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<li><span class="t-spar">lhs</span> 与 <span class="t-spar">rhs</span> 均拥有<a href="c-language-arithmetic_types.html">算术类型</a>，此情况下 <span class="t-spar">lhs</span> 可为<a href="c-language-volatile.html">volatile</a> 限定或<a href="c-language-atomic.html">原子的</a></li>
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<li><span class="t-spar">lhs</span> 与 <span class="t-spar">rhs</span> 均拥有指向<a href="c-language-types.html#.E5.85.BC.E5.AE.B9.E7.B1.BB.E5.9E.8B">兼容</a>类型的<a href="c-language-pointer.html">指针</a>类型，或其中一个指针是指向 void 的指针，而<a href="c-language-conversion.html">转换</a>不为被指向类型添加限定符。 <span class="t-spar">lhs</span> 可以为 <a href="c-language-volatile.html">volatile</a> 或 <a href="c-language-restrict.html">restrict</a> 限定，或<a href="c-language-atomic.html">原子的</a>。</li>
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<li><span class="t-spar">lhs</span> 是指针（可以有限定或是原子的），而 <span class="t-spar">rhs</span> 是空指针常量，如 <span class="t-lc"><a href="c-types-NULL.html">NULL</a></span> 。</li>
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<li><span class="t-spar">lhs</span> 拥有类型 <span class="t-lc">_Bool</span>（可以有限定或是原子的）而 <span class="t-spar">rhs</span> 是指针 。</li>
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</ul>
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</dd>
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</dl>
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<h4><span class="mw-headline" id=".E6.B3.A8.E6.84.8F">注意</span></h4>
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<p>若 <span class="t-spar">rhs</span> 与 <span class="t-spar">lhs</span> 在内存中重叠（例如它们是同一联合体的成员），则行为未定义，除非重叠是准确的且两者类型<a href="c-language-type.html#.E5.85.BC.E5.AE.B9.E7.B1.BB.E5.9E.8B" class="mw-redirect">兼容</a>。</p>
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<p>尽管数组不可赋值，但包裹在结构体内的数组可以赋值给另一个相同（或兼容）的结构体类型。</p>
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<p>更新 <span class="t-spar">lhs</span> 的副效应<a href="c-language-eval_order.html">后序于</a>值计算，但 <span class="t-spar">lhs</span> 和 <span class="t-spar">rhs</span> 自己和运算数的求值不是，与通常一样，它们相对于彼此是不定序的（故如 <span class="t-c"><span class="mw-geshi c source-c">i<span class="sy1">=</span><span class="sy2">++</span>i</span></span> 的表达式是未定义的）</p>
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<p>赋值会剥除浮点表达式的额外范围和精度（见 <span class="t-lc"><a href="c-types-limits-FLT_EVAL_METHOD.html">FLT_EVAL_METHOD</a></span> ）。</p>
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<p>C++ 中，赋值运算符是左值表达式，而 C 中不是</p>
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<div class="t-example">
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<div class="t-example-live-link"></div>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="c source-c">
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<pre class="de1"><span class="co2">#include <stdio.h></span>
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<span class="kw4">int</span> main<span class="br0">(</span><span class="kw4">void</span><span class="br0">)</span>
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<span class="br0">{</span>
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<span class="kw4">const</span> <span class="kw4">char</span> <span class="sy2">**</span>cpp<span class="sy4">;</span>
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<span class="kw4">char</span> <span class="sy2">*</span>p<span class="sy4">;</span>
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<span class="kw4">const</span> <span class="kw4">char</span> c <span class="sy1">=</span> <span class="st0">'A'</span><span class="sy4">;</span>
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<span class="co1">// cpp = &p; // 错误： char** 不能转换为 const char**</span>
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<span class="sy2">*</span>cpp <span class="sy1">=</span> <span class="sy3">&</span>c<span class="sy4">;</span> <span class="co1">// OK ： char* 能转换为 const char*</span>
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<span class="sy2">*</span>p <span class="sy1">=</span> <span class="nu0">0</span><span class="sy4">;</span> <span class="co1">// OK ：空指针常量能转换为任何指针</span>
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<span class="kw4">int</span> arr1<span class="br0">[</span><span class="nu0">2</span><span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">1</span>,<span class="nu0">2</span><span class="br0">}</span>, arr2<span class="br0">[</span><span class="nu0">2</span><span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">3</span>, <span class="nu0">4</span><span class="br0">}</span><span class="sy4">;</span>
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<span class="co1">// arr1 = arr2; // 错误：不能通过数组赋值</span>
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<span class="kw1">struct</span> s <span class="br0">{</span>
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<span class="kw4">int</span> arr<span class="br0">[</span><span class="nu0">2</span><span class="br0">]</span><span class="sy4">;</span> <span class="co1">// 包装于结构体中的数组</span>
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<span class="br0">}</span> sam1 <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">5</span>, <span class="nu0">6</span><span class="br0">}</span>, sam2 <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">7</span>, <span class="nu0">8</span><span class="br0">}</span><span class="sy4">;</span>
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sam1 <span class="sy1">=</span> sam2<span class="sy4">;</span> <span class="co1">// OK ：能赋值包装于结构体中的数组</span>
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<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">"%d %d <span class="es1">\n</span>"</span>,sam1.<span class="me1">arr</span><span class="br0">[</span><span class="nu0">0</span><span class="br0">]</span>,sam1.<span class="me1">arr</span><span class="br0">[</span><span class="nu0">1</span><span class="br0">]</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="br0">}</span></pre></div>
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</div>
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<p>输出：</p>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="text source-text">
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<pre class="de1">7 8</pre></div>
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</div>
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</div>
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<h3><span class="mw-headline" id=".E5.A4.8D.E5.90.88.E8.B5.8B.E5.80.BC">复合赋值</span></h3>
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<p>复合赋值运算符表达式拥有形式</p>
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<table class="t-sdsc-begin">
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<tr>
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<td colspan="10" class="t-sdsc-sep"></td>
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</tr>
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<tr class="t-sdsc">
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<td class="t-sdsc-nopad"><span class="t-spar">lhs</span> <span class="t-spar">op</span> <span class="t-spar">rhs</span></td>
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<td class="t-sdsc-nopad"></td>
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<td class="t-sdsc-nopad"></td>
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</tr>
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<tr>
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<td colspan="10" class="t-sdsc-sep"></td>
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</tr>
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</table>
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<p>其中</p>
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<table class="t-par-begin">
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<tr class="t-par">
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<td><span class="t-spar">op</span></td>
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<td>-</td>
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<td>one of <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">*</span><span class="sy1">=</span></span></span>, <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">/</span><span class="sy1">=</span></span></span> <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">%</span><span class="sy1">=</span></span></span>, <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">+</span><span class="sy1">=</span></span></span> <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">-</span><span class="sy1">=</span></span></span>, <span class="t-c"><span class="mw-geshi c source-c"><span class="sy1"><<=</span></span></span>, <span class="t-c"><span class="mw-geshi c source-c"><span class="sy1">>>=</span></span></span>, <span class="t-c"><span class="mw-geshi c source-c"><span class="sy3">&</span><span class="sy1">=</span></span></span>, <span class="t-c"><span class="mw-geshi c source-c"><span class="sy3">^</span><span class="sy1">=</span></span></span>, <span class="t-c"><span class="mw-geshi c source-c"><span class="sy3">|</span><span class="sy1">=</span></span></span></td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td><span class="t-spar">lhs</span>, <span class="t-spar">rhs</span></td>
|
|
<td>-</td>
|
|
<td>拥有<a href="c-language-arithmetic_types.html">算术类型</a>的表达式（其中 <span class="t-spar">lhs</span> 可以有限定或是原子的），除非 <span class="t-spar">op</span> 是 <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">+</span><span class="sy1">=</span></span></span> 或 <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">-</span><span class="sy1">=</span></span></span> ，此情况允许接受拥有与 + 和 - 相同限制的指针类型</td>
|
|
</tr>
|
|
</table>
|
|
<p>表达式 <span class="t-spar">lhs</span> <span class="t-spar">@=</span> <span class="t-spar">rhs</span> 与 <span class="t-spar">lhs</span> <code><b>=</b></code> <span class="t-spar">lhs</span> <span class="t-spar">@</span> <code><b>(</b></code> <span class="t-spar">rhs</span> <code><b>)</b></code> 准确相同，除了只求值一次 <span class="t-spar">lhs</span> 。</p>
|
|
<table class="t-rev-begin">
|
|
<tr class="t-rev t-since-c11">
|
|
<td>
|
|
<p>若 <span class="t-spar">lhs</span> 拥有<a href="c-language-atomic.html">原子</a>类型，则运算表现为单个带内存顺序 <span class="t-lc"><a href="c-atomic-memory_order.html">memory_order_seq_cst</a></span> 的原子读修改写操作</p>
|
|
<p>对于整数原子类型，复合赋值运算 <span class="t-c"><span class="mw-geshi c source-c">@<span class="sy1">=</span></span></span> 等价于：</p>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="c source-c">
|
|
<pre class="de1">T1<span class="sy2">*</span> addr <span class="sy1">=</span> <span class="sy3">&</span>lhs<span class="sy4">;</span>
|
|
T2 val <span class="sy1">=</span> rhs<span class="sy4">;</span>
|
|
T1 old <span class="sy1">=</span> <span class="sy2">*</span>addr<span class="sy4">;</span>
|
|
T1 new<span class="sy4">;</span>
|
|
<span class="kw1">do</span> <span class="br0">{</span> new <span class="sy1">=</span> old @ val <span class="br0">}</span> <span class="kw1">while</span> <span class="br0">(</span><span class="sy3">!</span><a href="c-atomic-atomic_compare_exchange.html"><span class="kw945">atomic_compare_exchange_strong</span></a><span class="br0">(</span>addr, <span class="sy3">&</span>old, new<span class="br0">)</span><span class="sy4">;</span></pre></div>
|
|
</div>
|
|
</td>
|
|
<td><span class="t-mark-rev t-since-c11">(C11 起)</span></td>
|
|
</tr>
|
|
</table>
|
|
<table class="metadata plainlinks ambox mbox-small-left ambox-notice" style="">
|
|
<tr>
|
|
<td class="mbox-empty-cell"></td>
|
|
<td class="mbox-text" style="">本节未完成<br />
|
|
原因：暂无示例</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E5.BC.95.E7.94.A8">引用</span></h3>
|
|
<div class="t-ref-std-11">
|
|
<ul>
|
|
<li>C11 标准（ISO/IEC 9899:2011）：</li>
|
|
</ul>
|
|
<dl>
|
|
<dd>
|
|
<ul>
|
|
<li>6.5.16 Assignment operators (p: 101-104)</li>
|
|
</ul>
|
|
</dd>
|
|
</dl>
|
|
<div class="t-ref-std-c99">
|
|
<ul>
|
|
<li>C99 标准（ISO/IEC 9899:1999）：</li>
|
|
</ul>
|
|
<dl>
|
|
<dd>
|
|
<ul>
|
|
<li>6.5.16 Assignment operators (p: 91-93)</li>
|
|
</ul>
|
|
</dd>
|
|
</dl>
|
|
<div class="t-ref-std-c89">
|
|
<ul>
|
|
<li>C89/C90 标准（ISO/IEC 9899:1990）：</li>
|
|
</ul>
|
|
<dl>
|
|
<dd>
|
|
<ul>
|
|
<li>3.3.16 Assignment operators</li>
|
|
</ul>
|
|
</dd>
|
|
</dl>
|
|
</div>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
|
|
<p><a href="c-language-operator_precedence.html">运算符优先级</a></p>
|
|
<table class="wikitable">
|
|
<tr style="text-align:center">
|
|
<th colspan="7">常用运算符</th>
|
|
</tr>
|
|
<tr style="text-align:center">
|
|
<td><strong class="selflink">赋值</strong></td>
|
|
<td><a href="c-language-operator_incdec.html">自增<br />
|
|
自减</a></td>
|
|
<td><a href="c-language-operator_arithmetic.html">算术</a></td>
|
|
<td><a href="c-language-operator_logical.html">逻辑</a></td>
|
|
<td><a href="c-language-operator_comparison.html">比较</a></td>
|
|
<td><a href="c-language-operator_member_access.html">成员<br />
|
|
访问</a></td>
|
|
<td><a href="c-language-operator_other.html">其他</a></td>
|
|
</tr>
|
|
<tr style="text-align:center">
|
|
<td>
|
|
<p><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">=</span> b<br />
|
|
a <span class="sy2">+</span><span class="sy1">=</span> b<br />
|
|
a <span class="sy2">-</span><span class="sy1">=</span> b<br />
|
|
a <span class="sy2">*</span><span class="sy1">=</span> b<br />
|
|
a <span class="sy2">/</span><span class="sy1">=</span> b<br />
|
|
a <span class="sy2">%</span><span class="sy1">=</span> b<br />
|
|
a <span class="sy3">&</span><span class="sy1">=</span> b<br />
|
|
a <span class="sy3">|</span><span class="sy1">=</span> b<br />
|
|
a <span class="sy3">^</span><span class="sy1">=</span> b<br />
|
|
a <span class="sy1"><<=</span> b<br />
|
|
a <span class="sy1">>>=</span> b</span></span></p>
|
|
</td>
|
|
<td>
|
|
<p><span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">++</span>a<br />
|
|
<span class="sy2">--</span>a<br />
|
|
a<span class="sy2">++</span><br />
|
|
a<span class="sy2">--</span></span></span></p>
|
|
</td>
|
|
<td>
|
|
<p><span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">+</span>a<br />
|
|
<span class="sy2">-</span>a<br />
|
|
a <span class="sy2">+</span> b<br />
|
|
a <span class="sy2">-</span> b<br />
|
|
a <span class="sy2">*</span> b<br />
|
|
a <span class="sy2">/</span> b<br />
|
|
a <span class="sy2">%</span> b<br />
|
|
~a<br />
|
|
a <span class="sy3">&</span> b<br />
|
|
a <span class="sy3">|</span> b<br />
|
|
a <span class="sy3">^</span> b<br />
|
|
a <span class="sy1"><<</span> b<br />
|
|
a <span class="sy1">>></span> b</span></span></p>
|
|
</td>
|
|
<td>
|
|
<p><span class="t-c"><span class="mw-geshi c source-c"><span class="sy3">!</span>a<br />
|
|
a <span class="sy3">&&</span> b<br />
|
|
a <span class="sy3">||</span> b</span></span></p>
|
|
</td>
|
|
<td>
|
|
<p><span class="t-c"><span class="mw-geshi c source-c">a <span class="sy1">==</span> b<br />
|
|
a <span class="sy3">!</span><span class="sy1">=</span> b<br />
|
|
a <span class="sy1"><</span> b<br />
|
|
a <span class="sy1">></span> b<br />
|
|
a <span class="sy1"><=</span> b<br />
|
|
a <span class="sy1">>=</span> b</span></span></p>
|
|
</td>
|
|
<td>
|
|
<p><span class="t-c"><span class="mw-geshi c source-c">a<span class="br0">[</span>b<span class="br0">]</span><br />
|
|
<span class="sy2">*</span>a<br />
|
|
<span class="sy3">&</span>a<br />
|
|
a<span class="sy2">-</span><span class="sy1">></span>b<br />
|
|
a.<span class="me1">b</span></span></span></p>
|
|
</td>
|
|
<td>
|
|
<p><span class="t-c"><span class="mw-geshi c source-c">a<span class="br0">(</span>...<span class="br0">)</span><br />
|
|
a, b<br />
|
|
<span class="br0">(</span>type<span class="br0">)</span> a<br />
|
|
<span class="sy4">?</span> <span class="sy4">:</span><br />
|
|
<span class="kw4">sizeof</span><br />
|
|
_Alignof</span></span> <span class="t-mark-rev t-since-c11">(C11 起)</span></p>
|
|
</td>
|
|
</tr>
|
|
</table>
|
|
<table class="t-dsc-begin"></table>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|