356 lines
28 KiB
HTML
356 lines
28 KiB
HTML
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<title>std::basic_string<CharT,Traits,Allocator>::operator=</title>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::basic_string<CharT,Traits,Allocator>::</span>operator=</h1>
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<div id="bodyContent">
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-string.html">string</a>‎ | <a href="cpp-string-basic_string.html">basic string</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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<td></td>
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<td rowspan="142">(1)</td>
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<td></td>
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</tr>
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<tr class="t-dcl t-until-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> str <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> str <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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</tbody>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<td rowspan="142">(2)</td>
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<td></td>
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<tr class="t-dcl t-since-cxx11 t-until-cxx17">
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<td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> basic_string<span class="sy3">&&</span> str <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark-rev t-until-cxx17">(C++17 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx17 t-until-cxx20">
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> basic_string<span class="sy3">&&</span> str <span class="br0">)</span> <span class="kw1">noexcept</span><span class="br0">(</span><span class="coMULTI">/* see below */</span><span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span><br />
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<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="sy3">&</span><br />
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operator<span class="sy1">=</span><span class="br0">(</span> basic_string<span class="sy3">&&</span> str <span class="br0">)</span> <span class="kw1">noexcept</span><span class="br0">(</span><span class="coMULTI">/* see below */</span><span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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</tbody>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<td rowspan="142">(3)</td>
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<td></td>
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<tr class="t-dcl t-until-cxx20">
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> s <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> s <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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</tbody>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<td rowspan="142">(4)</td>
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<td></td>
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<tr class="t-dcl t-until-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> CharT ch <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> CharT ch <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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</tr>
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</tbody>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<tr class="t-dcl-rev-aux">
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<td rowspan="142">(5)</td>
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<td></td>
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<tr class="t-dcl t-since-cxx11 t-until-cxx20">
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>CharT<span class="sy1">></span> ilist <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> <a href="cpp-utility-initializer_list.html"><span class="kw960">std::<span class="me2">initializer_list</span></span></a><span class="sy1"><</span>CharT<span class="sy1">></span> ilist <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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</tr>
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</tbody>
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<tbody></tbody>
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<tbody class="t-dcl-rev t-dcl-rev-num">
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<td></td>
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<td rowspan="142">(6)</td>
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<td></td>
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<tr class="t-dcl t-since-cxx17 t-until-cxx20">
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T<span class="sy1">></span><br />
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basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> t <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span><br />
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<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx20">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T<span class="sy1">></span><br />
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<span class="kw4">constexpr</span> basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> t <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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</tr>
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</tbody>
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<tbody>
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<tr class="t-dcl t-since-cxx23">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> basic_string<span class="sy3">&</span> operator<span class="sy1">=</span><span class="br0">(</span> <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a> <span class="br0">)</span> <span class="sy1">=</span> delete<span class="sy4">;</span></span></div>
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</td>
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<td>(7)</td>
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<td><span class="t-mark-rev t-since-cxx23">(C++23 起)</span></td>
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</tr>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</table>
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<p>替换字符串的内容。</p>
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<div class="t-li1"><span class="t-li">1)</span> 以 <code>str</code> 的副本替换内容。若 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> 与 <code>str</code> 为同一对象，则此函数无效果。</div>
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<div class="t-li1"><span class="t-li">2)</span> 用移动语义以 <code>str</code> 的内容替换内容。之后 <code>str</code> 在合法但未指定的状态。若 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-memory-allocator_traits.html"><span class="kw701">std::<span class="me2">allocator_traits</span></span></a><span class="sy1"><</span>Allocator<span class="sy1">></span><span class="sy4">::</span><span class="me2">propagate_on_container_move_assignment</span><span class="sy4">::</span><span class="me2">value</span></span></span> 为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> ，则以 <code>str</code> 的分配器副本替换 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> 的。若它为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> 且 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> 与 <code>str</code> 的分配器不比较相等，则 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> 不能接收 <code>str</code> 所拥有的内存的所有权，而必须逐个字符赋值，用其自身的分配器按需分配额外内存。不同于其他容器移动赋值，指向 <code>str</code> 的引用、指针和迭代器可能被无效化。</div>
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<div class="t-li1"><span class="t-li">3)</span> 以 <code>s</code> 所指向的空终止字符串的内容替换内容，如同用 <span class="t-c"><span class="mw-geshi cpp source-cpp">assign<span class="br0">(</span>s, Traits<span class="sy4">::</span><span class="me2">length</span><span class="br0">(</span>s<span class="br0">)</span><span class="br0">)</span></span></span> 。</div>
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<div class="t-li1"><span class="t-li">4)</span> 以字符 <code>ch</code> 的内容替换内容，如同用 <span class="t-c"><span class="mw-geshi cpp source-cpp">assign<span class="br0">(</span><a href="cpp-memory-addressof.html"><span class="kw757">std::<span class="me2">addressof</span></span></a><span class="br0">(</span>ch<span class="br0">)</span>, <span class="nu0">1</span><span class="br0">)</span></span></span> 。</div>
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<div class="t-li1"><span class="t-li">5)</span> 以 initializer_list <code>ilist</code> 的内容替换内容，如同用 <span class="t-c"><span class="mw-geshi cpp source-cpp">assign<span class="br0">(</span>ilist.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, ilist.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span> 。</div>
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<div class="t-li1"><span class="t-li">6)</span> 如同用 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string_view.html"><span class="kw1246">std::<span class="me2">basic_string_view</span></span></a><span class="sy1"><</span>CharT, Traits<span class="sy1">></span> sv <span class="sy1">=</span> t<span class="sy4">;</span></span></span> 隐式转换 <code>t</code> 为 string_view <code>sv</code> ，然后如同用 <span class="t-c"><span class="mw-geshi cpp source-cpp">assign<span class="br0">(</span>sv<span class="br0">)</span></span></span> ，以 <code>sv</code> 的内容替换内容。此重载仅若 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-is_convertible.html"><span class="kw593">std::<span class="me2">is_convertible_v</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <a href="cpp-string-basic_string_view.html"><span class="kw1246">std::<span class="me2">basic_string_view</span></span></a><span class="sy1"><</span>CharT, Traits<span class="sy1">>></span></span></span> 为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 且 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-is_convertible.html"><span class="kw593">std::<span class="me2">is_convertible_v</span></span></a><span class="sy1"><</span><span class="kw4">const</span> T<span class="sy3">&</span>, <span class="kw4">const</span> CharT<span class="sy2">*</span><span class="sy1">></span></span></span> 为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> 才参与重载决议。</div>
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<div class="t-li1"><span class="t-li">7)</span> 不能将 <span class="t-c"><span class="mw-geshi cpp source-cpp">nullptr</span></span> 赋值给 <code>basic_string</code> 。</div>
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<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
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<table class="t-par-begin">
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<tr class="t-par">
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<td>ch</td>
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<td>-</td>
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<td>用以初始化 string 的字符</td>
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</tr>
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<tr class="t-par">
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<td>str</td>
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<td>-</td>
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<td>用作源初始化 string 的 string</td>
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</tr>
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<tr class="t-par">
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<td>s</td>
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<td>-</td>
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<td>指向空终止字符串的指针，用作源初始化 string</td>
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</tr>
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<tr class="t-par">
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<td>init</td>
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<td>-</td>
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<td>用作源初始化 string 的 <span class="t-lc"><a href="cpp-utility-initializer_list.html">std::initializer_list</a></span></td>
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</tr>
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<tr class="t-par">
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<td>t</td>
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<td>-</td>
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<td>可转换为用以初始化 string 的 <span class="t-lc"><a href="cpp-string-basic_string_view.html">std::basic_string_view</a></span> 的对象</td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">返回值</span></h3>
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<p><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span></p>
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<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">复杂度</span></h3>
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<div class="t-li1"><span class="t-li">1)</span> 与 <code>str</code> 的大小成线性。</div>
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<div class="t-li1"><span class="t-li">2)</span> 与 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> 的大小成线性（正式而言，必须销毁每个 <code>CharT</code> ）。若分配器比较不相等且不传播，则亦与 <code>str</code> 的大小成线性（必须进行复制）。</div>
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<div class="t-li1"><span class="t-li">3)</span> 与 <code>s</code> 的大小成线性。</div>
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<div class="t-li1"><span class="t-li">4)</span> 常数。</div>
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<div class="t-li1"><span class="t-li">5)</span> 与 <code>init</code> 的大小成线性。</div>
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<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">异常</span></h3>
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<table class="t-rev-begin">
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<tr class="t-rev t-since-cxx17">
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<td>
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<div class="t-li1"><span class="t-li">2)</span>
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<div class="t-noexcept-full"><a href="cpp-language-noexcept_spec.html"><tt>noexcept</tt></a> 说明：
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<div class="t-noexcept-box"><span class="t-cc"><span class="mw-geshi cpp source-cpp"><span class="kw1">noexcept</span><span class="br0">(</span><a href="cpp-memory-allocator_traits.html"><span class="kw701">std::<span class="me2">allocator_traits</span></span></a><span class="sy1"><</span>Allocator<span class="sy1">></span><span class="sy4">::</span><span class="me2">propagate_on_container_move_assignment</span><span class="sy4">::</span><span class="me2">value</span><br />
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<span class="sy3">||</span> <a href="cpp-memory-allocator_traits.html"><span class="kw701">std::<span class="me2">allocator_traits</span></span></a><span class="sy1"><</span>Allocator<span class="sy1">></span><span class="sy4">::</span><span class="me2">is_always_equal</span><span class="sy4">::</span><span class="me2">value</span><span class="br0">)</span></span></span></div>
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</div>
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</div>
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</td>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></td>
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</tr>
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</table>
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<p>若操作将导致 <span class="t-c"><span class="mw-geshi cpp source-cpp">size<span class="br0">(</span><span class="br0">)</span> <span class="sy1">></span> max_size<span class="br0">(</span><span class="br0">)</span></span></span> ，则抛出 <span class="t-lc"><a href="cpp-error-length_error.html">std::length_error</a></span> 。</p>
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<table class="t-rev-begin">
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<tr class="t-rev t-since-cxx11">
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<td>
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<p>若因任何原因抛异常，则此函数无效果（强异常保证）。</p>
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</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
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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="cpp source-cpp">
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<pre class="de1"><span class="co2">#include <string></span>
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<span class="co2">#include <iostream></span>
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<span class="co2">#include <iomanip></span>
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|
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
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<span class="br0">{</span>
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<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> str1<span class="sy4">;</span>
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<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> str2 <span class="br0">{</span> <span class="st0">"alpha"</span> <span class="br0">}</span><span class="sy4">;</span>
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<span class="co1">// (1) operator=( const basic_string& );</span>
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str1 <span class="sy1">=</span> str2<span class="sy4">;</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>str1<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">' '</span> <span class="co1">// "alpha"</span>
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<span class="sy1"><<</span> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>str2<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "alpha"</span>
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<span class="co1">// (2) operator=( basic_string&& );</span>
|
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str1 <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span>str2<span class="br0">)</span><span class="sy4">;</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>str1<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">' '</span> <span class="co1">// "alpha"</span>
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<span class="sy1"><<</span> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>str2<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "" 或 "alpha" （未指定）</span>
|
|
|
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<span class="co1">// (3) operator=( const CharT* );</span>
|
|
str1 <span class="sy1">=</span> <span class="st0">"beta"</span><span class="sy4">;</span>
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|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>str1<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "beta"</span>
|
|
|
|
<span class="co1">// (4) operator=( CharT );</span>
|
|
str1 <span class="sy1">=</span> <span class="st0">'!'</span><span class="sy4">;</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>str1<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "!"</span>
|
|
|
|
<span class="co1">// (5) operator=( std::initializer_list<CharT> );</span>
|
|
str1 <span class="sy1">=</span> <span class="br0">{</span><span class="st0">'g'</span>,<span class="st0">'a'</span>,<span class="st0">'m'</span>,<span class="st0">'m'</span>,<span class="st0">'a'</span><span class="br0">}</span><span class="sy4">;</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>str1<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "gamma"</span>
|
|
|
|
<span class="co1">// (6) operator=( const T& );</span>
|
|
str1 <span class="sy1">=</span> 35U<span class="sy4">;</span> <span class="co1">// equivalent to str1 = static_cast<char>(35U);</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-quoted.html"><span class="kw1802">std::<span class="me2">quoted</span></span></a><span class="br0">(</span>str1<span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span> <span class="co1">// "#" (ASCII = 35)</span>
|
|
<span class="br0">}</span></pre></div>
|
|
</div>
|
|
<p>可能的输出：</p>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="text source-text">
|
|
<pre class="de1">"alpha" "alpha"
|
|
"alpha" ""
|
|
"beta"
|
|
"!"
|
|
"gamma"
|
|
"#"</pre></div>
|
|
</div>
|
|
</div>
|
|
<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">缺陷报告</span></h3>
|
|
<p>下列更改行为的缺陷报告追溯地应用于以前出版的 C++ 标准。</p>
|
|
<table class="dsctable" style="font-size:0.8em">
|
|
<tr>
|
|
<th>DR</th>
|
|
<th>应用于</th>
|
|
<th>出版时的行为</th>
|
|
<th>正确行为</th>
|
|
</tr>
|
|
<tr>
|
|
<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue2063">LWG 2063</a></td>
|
|
<td>C++11</td>
|
|
<td>非规范性注释曾说交换是移动赋值的合法实现</td>
|
|
<td>更正以支持分配器</td>
|
|
</tr>
|
|
<tr>
|
|
<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue2946">LWG 2946</a></td>
|
|
<td>C++17</td>
|
|
<td><code>string_view</code> 重载在某些情况下导致歧义</td>
|
|
<td>通过使之为模板来避免</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div t-dsc-member-nobold-div">
|
|
<div><a href="cpp-string-basic_string-basic_string.html"><span class="t-lines"><span>(构造函数)</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>构造 <code>basic_string</code><br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-string-basic_string-assign.html"><span class="t-lines"><span>assign</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>赋值字符给字符串<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-string-basic_string_view-operator=.html"><span class="t-lines"><span>operator=</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>对视图赋值<br />
|
|
<span class="t-mark">(<code>std::basic_string_view<CharT,Traits></code> 的公开成员函数)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
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</html>
|