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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::literals::string_literals::</span>operator&quot;&quot;s</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-string.html">string</a>&lrm; | <a href="cpp-string-basic_string.html">basic string</a></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-string.html">&lt;string&gt;</a></code></div>
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<td rowspan="142">(1)</td>
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<div><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> operator<span class="st0">&quot;&quot;</span>s<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char</span> <span class="sy2">*</span>str, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> len<span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 &#36215;)</span><br />
<span class="t-mark-rev t-until-cxx20">(C++20 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> operator<span class="st0">&quot;&quot;</span>s<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char</span> <span class="sy2">*</span>str, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> len<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 &#36215;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> std<span class="sy4">::</span><span class="me2">u8string</span> operator<span class="st0">&quot;&quot;</span>s<span class="br0">(</span><span class="kw4">const</span> char8_t <span class="sy2">*</span>str, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> len<span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(2)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
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<td rowspan="142">(3)</td>
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<div><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string.html"><span class="kw1234">std::<span class="me2">u16string</span></span></a> operator<span class="st0">&quot;&quot;</span>s<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char16_t</span> <span class="sy2">*</span>str, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> len<span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 &#36215;)</span><br />
<span class="t-mark-rev t-until-cxx20">(C++20 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <a href="cpp-string-basic_string.html"><span class="kw1234">std::<span class="me2">u16string</span></span></a> operator<span class="st0">&quot;&quot;</span>s<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char16_t</span> <span class="sy2">*</span>str, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> len<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 &#36215;)</span></td>
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<td rowspan="142">(4)</td>
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<div><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string.html"><span class="kw1236">std::<span class="me2">u32string</span></span></a> operator<span class="st0">&quot;&quot;</span>s<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char32_t</span> <span class="sy2">*</span>str, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> len<span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 &#36215;)</span><br />
<span class="t-mark-rev t-until-cxx20">(C++20 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <a href="cpp-string-basic_string.html"><span class="kw1236">std::<span class="me2">u32string</span></span></a> operator<span class="st0">&quot;&quot;</span>s<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char32_t</span> <span class="sy2">*</span>str, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> len<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 &#36215;)</span></td>
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<td rowspan="142">(5)</td>
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<div><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string.html"><span class="kw1232">std::<span class="me2">wstring</span></span></a> operator<span class="st0">&quot;&quot;</span>s<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">wchar_t</span> <span class="sy2">*</span>str, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> len<span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 &#36215;)</span><br />
<span class="t-mark-rev t-until-cxx20">(C++20 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <a href="cpp-string-basic_string.html"><span class="kw1232">std::<span class="me2">wstring</span></span></a> operator<span class="st0">&quot;&quot;</span>s<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">wchar_t</span> <span class="sy2">*</span>str, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> len<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 &#36215;)</span></td>
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<p>&#21019;&#24314;&#25152;&#38656;&#31867;&#22411;&#30340; string &#23383;&#38754;&#37327;&#12290;</p>
<div class="t-li1"><span class="t-li">1)</span> &#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a><span class="br0">{</span>str, len<span class="br0">}</span></span></span></div>
<div class="t-li1"><span class="t-li">2)</span> &#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">u8string</span><span class="br0">{</span>str, len<span class="br0">}</span></span></span></div>
<div class="t-li1"><span class="t-li">3)</span> &#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string.html"><span class="kw1234">std::<span class="me2">u16string</span></span></a><span class="br0">{</span>str, len<span class="br0">}</span></span></span></div>
<div class="t-li1"><span class="t-li">4)</span> &#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string.html"><span class="kw1236">std::<span class="me2">u32string</span></span></a><span class="br0">{</span>str, len<span class="br0">}</span></span></span></div>
<div class="t-li1"><span class="t-li">5)</span> &#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string.html"><span class="kw1232">std::<span class="me2">wstring</span></span></a><span class="br0">{</span>str, len<span class="br0">}</span></span></span></div>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>str</td>
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<td>&#25351;&#21521;&#26080;&#20462;&#39280;&#23383;&#31526;&#25968;&#32452;&#23383;&#38754;&#37327;&#36215;&#22987;&#30340;&#25351;&#38024;</td>
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<td>len</td>
<td>-</td>
<td>&#26080;&#20462;&#39280;&#23383;&#31526;&#25968;&#32452;&#23383;&#38754;&#37327;&#30340;&#38271;&#24230;</td>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p>string &#23383;&#38754;&#37327;&#12290;</p>
<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">&#27880;&#35299;</span></h3>
<p>&#36825;&#20123;&#36816;&#31639;&#31526;&#23450;&#20041;&#20110;&#21629;&#21517;&#31354;&#38388; <code>std::literals::string_literals</code> &#65292;&#20854;&#20013; <code>literals</code> &#21644; <code>string_literals</code> &#37117;&#26159;&#20869;&#32852;&#21629;&#21517;&#31354;&#38388;&#12290;&#21487;&#36890;&#36807; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">using</span> <span class="kw1">namespace</span> std<span class="sy4">::</span><span class="me2">literals</span></span></span> &#12289; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">using</span> <span class="kw1">namespace</span> std<span class="sy4">::</span><span class="me2">string_literals</span></span></span> &#21450; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">using</span> <span class="kw1">namespace</span> std<span class="sy4">::</span><span class="me2">literals</span><span class="sy4">::</span><span class="me2">string_literals</span></span></span> &#33719;&#21462;&#23545;&#36825;&#20123;&#36816;&#31639;&#31526;&#30340;&#35775;&#38382;&#12290;</p>
<p><span class="t-lc"><a href="cpp-chrono-duration.html">std::chrono::duration</a></span> &#20134;&#23450;&#20041; <code>operator&quot;&quot;s</code> &#65292;&#20197;&#34920;&#31034;&#23383;&#38754;&#37327;&#30340;&#31186;&#65292;&#20294;&#23427;&#26159;&#31639;&#26415;&#31867;&#22411;&#23383;&#38754;&#37327;&#65306; <span class="t-c"><span class="mw-geshi cpp source-cpp">10.0s</span></span> &#19982; <span class="t-c"><span class="mw-geshi cpp source-cpp">10s</span></span> &#26159;&#21313;&#31186;&#65292;&#20294; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&quot;10&quot;</span>s</span></span> &#26159;&#23383;&#31526;&#20018;&#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
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<pre class="de1"><span class="co2">#include &lt;string&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="kw1">using</span> <span class="kw1">namespace</span> std<span class="sy4">::</span><span class="me2">string_literals</span><span class="sy4">;</span>
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s1 <span class="sy1">=</span> <span class="st0">&quot;abc<span class="es5">\0</span><span class="es5">\0</span>def&quot;</span><span class="sy4">;</span>
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s2 <span class="sy1">=</span> <span class="st0">&quot;abc<span class="es5">\0</span><span class="es5">\0</span>def&quot;</span>s<span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;s1: &quot;</span> <span class="sy1">&lt;&lt;</span> s1.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot; <span class="es1">\&quot;</span>&quot;</span> <span class="sy1">&lt;&lt;</span> s1 <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;<span class="es1">\&quot;</span><span class="es1">\n</span>&quot;</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">&lt;&lt;</span> <span class="st0">&quot;s2: &quot;</span> <span class="sy1">&lt;&lt;</span> s2.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot; <span class="es1">\&quot;</span>&quot;</span> <span class="sy1">&lt;&lt;</span> s2 <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;<span class="es1">\&quot;</span><span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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<p>&#21487;&#33021;&#30340;&#36755;&#20986;&#65306;</p>
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<pre class="de1">s1: 3 &quot;abc&quot;
s2: 8 &quot;abcdef&quot;</pre></div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
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<div><a href="cpp-string-basic_string-basic_string.html"><span class="t-lines"><span>(&#26500;&#36896;&#20989;&#25968;)</span></span></a></div>
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<td>&#26500;&#36896; <code>basic_string</code><br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-string-basic_string_view-operator_22_22sv.html"><span class="t-lines"><span>operator&quot;&quot;sv</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
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<td>&#21019;&#24314;&#19968;&#20010;&#23383;&#31526;&#25968;&#32452;&#23383;&#38754;&#37327;&#30340;&#23383;&#31526;&#20018;&#35270;&#22270;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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