449 lines
32 KiB
HTML
449 lines
32 KiB
HTML
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<title>std::basic_string<CharT,Traits,Allocator>::append</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>append</h1>
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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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<td rowspan="142">(1)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> append<span class="br0">(</span> size_type count, CharT ch <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><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> append<span class="br0">(</span> size_type count, CharT ch <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(2)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> append<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><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> append<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><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(3)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> append<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> str,<br />
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size_type pos, size_type count <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-until-cxx14">(C++14 前)</span></td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> append<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> str,<br />
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size_type pos, size_type count <span class="sy1">=</span> npos <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 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> append<span class="br0">(</span> <span class="kw4">const</span> basic_string<span class="sy3">&</span> str,<br />
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size_type pos, size_type count <span class="sy1">=</span> npos <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(4)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> append<span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type count <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><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> append<span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type count <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(5)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> append<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><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
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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> append<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><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(6)</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> InputIt <span class="sy1">></span><br />
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basic_string<span class="sy3">&</span> append<span class="br0">(</span> InputIt first, InputIt last <span class="br0">)</span><span class="sy4">;</span></span></div>
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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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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> InputIt <span class="sy1">></span><br />
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<span class="kw4">constexpr</span> basic_string<span class="sy3">&</span> append<span class="br0">(</span> InputIt first, InputIt last <span class="br0">)</span><span class="sy4">;</span></span></div>
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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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<td rowspan="142">(7)</td>
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<div><span class="mw-geshi cpp source-cpp">basic_string<span class="sy3">&</span> append<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 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 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> append<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 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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<td rowspan="142">(8)</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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basic_string<span class="sy3">&</span> append<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 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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<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> append<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><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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<td rowspan="142">(9)</td>
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<td></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 /></span>
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<p>basic_string<span class="sy3">&</span> append<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> t,<br /></p>
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size_type pos, size_type count <span class="sy1">=</span> npos <span class="br0">)</span><span class="sy4">;</span></div>
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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 class="t-dcl t-since-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 /></span>
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<p><span class="kw4">constexpr</span> basic_string<span class="sy3">&</span> append<span class="br0">(</span> <span class="kw4">const</span> T<span class="sy3">&</span> t,<br /></p>
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size_type pos, size_type count <span class="sy1">=</span> npos <span class="br0">)</span><span class="sy4">;</span></div>
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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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<p>后附额外字符到字符串。</p>
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<div class="t-li1"><span class="t-li">1)</span> 后附 <code>count</code> 个 <code>ch</code> 的副本</div>
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<div class="t-li1"><span class="t-li">2)</span> 后附 string <code>str</code></div>
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<div class="t-li1"><span class="t-li">3)</span> 后附 <code>str</code> 的子串 <code>[pos, pos+count)</code> 。若请求的子串越过 string 结尾，或若 <span class="t-c"><span class="mw-geshi cpp source-cpp">count <span class="sy1">==</span> npos</span></span> ，则后附的子串为 <code>[pos, size())</code> 。若 <span class="t-c"><span class="mw-geshi cpp source-cpp">pos <span class="sy1">></span> str.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span></span></span> ，则抛出 <span class="t-lc"><a href="cpp-error-out_of_range.html">std::out_of_range</a></span> 。</div>
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<div class="t-li1"><span class="t-li">4)</span> 后附范围 <code>[s, s + count)</code> 中的字符。此范围能含有空字符。</div>
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<div class="t-li1"><span class="t-li">5)</span> 后附 <code>s</code> 所指向的空终止字符串。由首个空字符用 <span class="t-c"><span class="mw-geshi cpp source-cpp">Traits<span class="sy4">::</span><span class="me2">length</span><span class="br0">(</span>s<span class="br0">)</span></span></span> 确定字符串的长度。</div>
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<div class="t-li1"><span class="t-li">6)</span> 后附范围 <code>[first, last)</code> 中的字符。
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<p>若 <code>InputIt</code> 为整数类型，则此重载与重载 <span class="t-v">(1)</span> 拥有相同效果。</p>
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<td><span class="t-mark-rev t-until-cxx11">(C++11 前)</span></td>
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<p>此重载仅若 <code>InputIt</code> 满足 <a href="cpp-named_req-InputIterator.html"><span style="font-style:italic">老式输入迭代器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LegacyInputIterator)</span></a> 的要求才参与重载决议。</p>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
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</div>
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<div class="t-li1"><span class="t-li">7)</span> 后附来自 initializer_list <code>ilist</code> 的字符。</div>
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<div class="t-li1"><span class="t-li">8)</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">append<span class="br0">(</span>sv.<span class="me1">data</span><span class="br0">(</span><span class="br0">)</span>, sv.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span> 后附所有来自 <code>sv</code> 的字符。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">9)</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> ，然后后附来自 <code>sv</code> 子视图 <code>[pos, pos+count)</code> 的字符。若请求的子视图越过 <code>sv</code> 的结尾，或若 <span class="t-c"><span class="mw-geshi cpp source-cpp">count <span class="sy1">==</span> npos</span></span> ，则后附的子视图为 <code>[pos, sv.size())</code> 。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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<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
|
|
<table class="t-par-begin">
|
|
<tr class="t-par">
|
|
<td>count</td>
|
|
<td>-</td>
|
|
<td>要后附的字符数</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>pos</td>
|
|
<td>-</td>
|
|
<td>要后附的首个字符下标</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>ch</td>
|
|
<td>-</td>
|
|
<td>要后附的字符值</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>first, last</td>
|
|
<td>-</td>
|
|
<td>要后附的字符范围</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>str</td>
|
|
<td>-</td>
|
|
<td>要后附的 string</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>s</td>
|
|
<td>-</td>
|
|
<td>指向要后附的字符串的指针</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>ilist</td>
|
|
<td>-</td>
|
|
<td>拥有要后附的字符的 initializer_list</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>t</td>
|
|
<td>-</td>
|
|
<td>可转换为带要后附的字符的 <span class="t-lc"><a href="cpp-string-basic_string_view.html">std::basic_string_view</a></span> 的对象</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">返回值</span></h3>
|
|
<p><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span></p>
|
|
<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">复杂度</span></h3>
|
|
<p>无标准复杂度保证，典型实现表现类似 <a href="cpp-container-vector-insert.html">std::vector::insert</a> 。</p>
|
|
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">异常</span></h3>
|
|
<p><span class="t-rev-inl t-since-cxx11"><span>若因任何原因抛出异常，则此函数无效果（强异常保证）。</span> <span><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></span></span></p>
|
|
<p>若操作会导致 <code>size() > max_size()</code> ，则抛出 <span class="t-lc"><a href="cpp-error-length_error.html">std::length_error</a></span> 。</p>
|
|
<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/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=".E7.A4.BA.E4.BE.8B">示例</span></h3>
|
|
<div class="t-example">
|
|
<div class="t-example-live-link"></div>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="cpp source-cpp">
|
|
<pre class="de1"><span class="co2">#include <string></span>
|
|
<span class="co2">#include <iostream></span>
|
|
|
|
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span> <span class="br0">{</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span><span class="kw4">char</span><span class="sy1">></span> str <span class="sy1">=</span> <span class="st0">"string"</span><span class="sy4">;</span>
|
|
<span class="kw4">const</span> <span class="kw4">char</span><span class="sy2">*</span> cptr <span class="sy1">=</span> <span class="st0">"C-string"</span><span class="sy4">;</span>
|
|
<span class="kw4">const</span> <span class="kw4">char</span> carr<span class="br0">[</span><span class="br0">]</span> <span class="sy1">=</span> <span class="st0">"Two and one"</span><span class="sy4">;</span>
|
|
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> output<span class="sy4">;</span>
|
|
|
|
<span class="co1">// 1) 后附 char 3 次。</span>
|
|
<span class="co1">// 注意，这是仅有的接受 char 的重载。</span>
|
|
output.<span class="me1">append</span><span class="br0">(</span><span class="nu0">3</span>, <span class="st0">'*'</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> <span class="st0">"1) "</span> <span class="sy1"><<</span> output <span class="sy1"><<</span> <span class="st0">"<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
|
|
<span class="co1">// 2) 后附整个 string</span>
|
|
output.<span class="me1">append</span><span class="br0">(</span>str<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> <span class="st0">"2) "</span> <span class="sy1"><<</span> output <span class="sy1"><<</span> <span class="st0">"<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
|
|
<span class="co1">// 3) 后附字符串的一部分（此情况为最后 3 个字母）case)</span>
|
|
output.<span class="me1">append</span><span class="br0">(</span>str, <span class="nu0">3</span>, <span class="nu0">3</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> <span class="st0">"3) "</span> <span class="sy1"><<</span> output <span class="sy1"><<</span> <span class="st0">"<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
|
|
<span class="co1">// 4) 后附 C 字符串的一部分</span>
|
|
<span class="co1">// 注意，因为 `append` 返回 *this ，我们能一同链式调用</span>
|
|
output.<span class="me1">append</span><span class="br0">(</span><span class="nu0">1</span>, <span class="st0">' '</span><span class="br0">)</span>.<span class="me1">append</span><span class="br0">(</span>carr, <span class="nu0">4</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> <span class="st0">"4) "</span> <span class="sy1"><<</span> output <span class="sy1"><<</span> <span class="st0">"<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
|
|
<span class="co1">// 5) 后附整个 C 字符串</span>
|
|
output.<span class="me1">append</span><span class="br0">(</span>cptr<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> <span class="st0">"5) "</span> <span class="sy1"><<</span> output <span class="sy1"><<</span> <span class="st0">"<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
|
|
<span class="co1">// 6) 后附范围</span>
|
|
output.<span class="me1">append</span><span class="br0">(</span><a href="cpp-iterator-begin.html"><span class="kw676">std::<span class="me2">begin</span></span></a><span class="br0">(</span>carr<span class="br0">)</span> <span class="sy2">+</span> <span class="nu0">3</span>, <a href="cpp-iterator-end.html"><span class="kw680">std::<span class="me2">end</span></span></a><span class="br0">(</span>carr<span class="br0">)</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> <span class="st0">"6) "</span> <span class="sy1"><<</span> output <span class="sy1"><<</span> <span class="st0">"<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
|
|
<span class="co1">// 7) 后附 initializer_list</span>
|
|
output.<span class="me1">append</span><span class="br0">(</span><span class="br0">{</span> <span class="st0">' '</span>, <span class="st0">'l'</span>, <span class="st0">'i'</span>, <span class="st0">'s'</span>, <span class="st0">'t'</span> <span class="br0">}</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> <span class="st0">"7) "</span> <span class="sy1"><<</span> output <span class="sy1"><<</span> <span class="st0">"<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
<span class="br0">}</span></pre></div>
|
|
</div>
|
|
<p>输出：</p>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="text source-text">
|
|
<pre class="de1">1) ***
|
|
2) ***string
|
|
3) ***stringing
|
|
4) ***stringing Two
|
|
5) ***stringing Two C-string
|
|
6) ***stringing Two C-string and one
|
|
7) ***stringing Two C-string and one list</pre></div>
|
|
</div>
|
|
</div>
|
|
<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">
|
|
<div><a href="cpp-string-basic_string-operator+=.html"><span class="t-lines"><span>operator+=</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>后附字符到结尾<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-byte-strcat.html"><span class="t-lines"><span>strcat</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>连接两个字符串<br />
|
|
<span class="t-mark">(函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-string-byte-strncat.html"><span class="t-lines"><span>strncat</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>连接两个字符串的一定量字符<br />
|
|
<span class="t-mark">(函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-string-wide-wcscat.html"><span class="t-lines"><span>wcscat</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>后附一个宽字符串的副本到另一个<br />
|
|
<span class="t-mark">(函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-string-wide-wcsncat.html"><span class="t-lines"><span>wcsncat</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>后附来自一个宽字符串的一定量宽字符到另一个<br />
|
|
<span class="t-mark">(函数)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|