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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">&#26631;&#20934;&#24211;&#22836;&#25991;&#20214;</span> &lt;string_view&gt;</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-header.html">header</a></span></div>
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<p>&#27492;&#22836;&#25991;&#20214;&#26159;<a href="cpp-string.html">&#23383;&#31526;&#20018;</a>&#24211;&#30340;&#19968;&#37096;&#20998;&#12290;</p>
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<h3><span class="mw-headline" id=".E5.8C.85.E5.90.AB">&#21253;&#21547;</span></h3>
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<div><a href="cpp-header-compare.html"><span class="t-lines"><span>&lt;compare&gt;</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td><a href="cpp-language-operator_comparison.html#.E4.B8.89.E8.B7.AF.E6.AF.94.E8.BE.83">&#19977;&#36335;&#27604;&#36739;&#36816;&#31639;&#31526;</a>&#25903;&#25345;</td>
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<td colspan="2">
<h3><span class="mw-headline" id=".E7.B1.BB">&#31867;</span></h3>
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<div><a href="cpp-string-basic_string_view.html"><span class="t-lines"><span>basic_string_view</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
</div>
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<td>&#21482;&#35835;&#30340;&#23383;&#31526;&#20018;&#35270;&#22270;<br />
<span class="t-mark">(&#31867;&#27169;&#26495;)</span></td>
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<td><span class="t-lc"><a href="cpp-string-basic_string_view.html">std::string_view</a></span> <span class="t-mark-rev t-since-cxx17">(C++17)</span></td>
<td><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">&lt;</span><span class="kw4">char</span><span class="sy1">&gt;</span></span></span></td>
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<td><span class="t-lc">std::u8string_view</span> <span class="t-mark-rev t-since-cxx20">(C++20)</span></td>
<td><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">&lt;</span>char8_t<span class="sy1">&gt;</span></span></span></td>
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<td><span class="t-lc"><a href="cpp-string-basic_string_view.html">std::u16string_view</a></span> <span class="t-mark-rev t-since-cxx17">(C++17)</span></td>
<td><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">&lt;</span><span class="kw4">char16_t</span><span class="sy1">&gt;</span></span></span></td>
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<td><span class="t-lc"><a href="cpp-string-basic_string_view.html">std::u32string_view</a></span> <span class="t-mark-rev t-since-cxx17">(C++17)</span></td>
<td><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">&lt;</span><span class="kw4">char32_t</span><span class="sy1">&gt;</span></span></span></td>
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<td><span class="t-lc"><a href="cpp-string-basic_string_view.html">std::wstring_view</a></span> <span class="t-mark-rev t-since-cxx17">(C++17)</span></td>
<td><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">&lt;</span><span class="kw4">wchar_t</span><span class="sy1">&gt;</span></span></span></td>
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<div><a href="cpp-string-basic_string_view-hash.html"><span class="t-lines"><span>std::hash<span class="t-dsc-small">&lt;std::string_view&gt;</span></span><span>std::hash<span class="t-dsc-small">&lt;std::wstring_view&gt;</span></span><span>std::hash<span class="t-dsc-small">&lt;std::u8string_view&gt;</span></span><span>std::hash<span class="t-dsc-small">&lt;std::u16string_view&gt;</span></span><span>std::hash<span class="t-dsc-small">&lt;std::u32string_view&gt;</span></span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
</div>
</td>
<td>string_view &#30340;&#25955;&#21015;&#25903;&#25345;<br />
<span class="t-mark">(&#31867;&#27169;&#26495;&#29305;&#21270;)</span></td>
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<tr>
<td colspan="2">
<h5><span class="mw-headline" id=".E5.89.8D.E7.BD.AE.E5.A3.B0.E6.98.8E">&#21069;&#32622;&#22768;&#26126;</span></h5>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-functional.html">&lt;functional&gt;</a></code></div>
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<div><a href="cpp-utility-hash.html"><span class="t-lines"><span>hash</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
</div>
</td>
<td>&#25955;&#21015;&#20989;&#25968;&#23545;&#35937;<br />
<span class="t-mark">(&#31867;&#27169;&#26495;)</span></td>
</tr>
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<td colspan="2">
<h3><span class="mw-headline" id=".E5.87.BD.E6.95.B0">&#20989;&#25968;</span></h3>
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<div class="t-dsc-member-div">
<div><a href="cpp-string-basic_string_view-operator_cmp.html"><span class="t-lines"><span>operator==</span><span>operator!=</span><span>operator&lt;</span><span>operator&gt;</span><span>operator&lt;=</span><span>operator&gt;=</span><span>operator&lt;=&gt;</span></span></a></div>
<div><span class="t-lines"><span></span><span><span class="t-mark-rev t-until-cxx20">(C++20 &#20013;&#31227;&#38500;)</span></span><span><span class="t-mark-rev t-until-cxx20">(C++20 &#20013;&#31227;&#38500;)</span></span><span><span class="t-mark-rev t-until-cxx20">(C++20 &#20013;&#31227;&#38500;)</span></span><span><span class="t-mark-rev t-until-cxx20">(C++20 &#20013;&#31227;&#38500;)</span></span><span><span class="t-mark-rev t-until-cxx20">(C++20 &#20013;&#31227;&#38500;)</span></span><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#20197;&#23383;&#20856;&#24207;&#27604;&#36739;&#20004;&#20010;&#23383;&#31526;&#20018;&#35270;&#22270;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-string-basic_string_view-operator_ltlt.html"><span class="t-lines"><span>operator&lt;&lt;</span></span></a></div>
</div>
</td>
<td>&#36827;&#34892;&#23383;&#31526;&#20018;&#35270;&#22270;&#30340;&#27969;&#36755;&#20986;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-algorithm-swap.html"><span class="t-lines"><span>swap</span></span></a></div>
</div>
</td>
<td>&#20132;&#25442;&#20004;&#20010;&#23545;&#35937;&#30340;&#20540;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
</tr>
<tr>
<td colspan="2">
<h5><span class="mw-headline" id=".E8.8C.83.E5.9B.B4.E8.AE.BF.E9.97.AE">&#33539;&#22260;&#35775;&#38382;</span></h5>
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<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-iterator-begin.html"><span class="t-lines"><span>begin</span><span>cbegin</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx14">(C++14)</span></span></span></div>
</div>
</td>
<td>&#36820;&#22238;&#25351;&#21521;&#23481;&#22120;&#25110;&#25968;&#32452;&#36215;&#22987;&#30340;&#36845;&#20195;&#22120;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-iterator-end.html"><span class="t-lines"><span>end</span><span>cend</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx14">(C++14)</span></span></span></div>
</div>
</td>
<td>&#36820;&#22238;&#25351;&#21521;&#23481;&#22120;&#25110;&#25968;&#32452;&#32467;&#23614;&#30340;&#36845;&#20195;&#22120;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
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<td>
<div class="t-dsc-member-div">
<div><a href="cpp-iterator-rbegin.html"><span class="t-lines"><span>rbegin</span><span>crbegin</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx14">(C++14)</span></span></span></div>
</div>
</td>
<td>&#36820;&#22238;&#25351;&#21521;&#19968;&#20010;&#23481;&#22120;&#25110;&#25968;&#32452;&#30340;&#36870;&#21521;&#36845;&#20195;&#22120;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
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<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-iterator-rend.html"><span class="t-lines"><span>rend</span><span>crend</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx14">(C++14)</span></span></span></div>
</div>
</td>
<td>&#36820;&#22238;&#23481;&#22120;&#25110;&#25968;&#32452;&#30340;&#36870;&#21521;&#23614;&#36845;&#20195;&#22120;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
</tr>
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<td>
<div class="t-dsc-member-div">
<div><a href="cpp-iterator-size.html"><span class="t-lines"><span>size</span><span>ssize</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#36820;&#22238;&#23481;&#22120;&#25110;&#25968;&#32452;&#30340;&#22823;&#23567;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-iterator-empty.html"><span class="t-lines"><span>empty</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
</div>
</td>
<td>&#26816;&#26597;&#23481;&#22120;&#26159;&#21542;&#20026;&#31354;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-iterator-data.html"><span class="t-lines"><span>data</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
</div>
</td>
<td>&#33719;&#24471;&#25351;&#21521;&#24213;&#23618;&#25968;&#32452;&#30340;&#25351;&#38024;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
</tr>
<tr>
<td colspan="2">
<h5><span class="mw-headline" id=".E5.AD.97.E9.9D.A2.E9.87.8F">&#23383;&#38754;&#37327;</span></h5>
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<tr class="t-dsc-header">
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<div>&#23450;&#20041;&#20110;&#20869;&#32852;&#21629;&#21517;&#31354;&#38388; <code>std::literals::string_view_literals</code></div>
</td>
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<td>
<div class="t-dsc-member-div">
<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>
</div>
</td>
<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>
</tr>
</table>
<h3><span class="mw-headline" id=".E6.A6.82.E8.A6.81">&#27010;&#35201;</span></h3>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="cpp source-cpp">
<pre class="de1"><span class="co2">#include &lt;compare&gt;</span>
<span class="kw1">namespace</span> std <span class="br0">{</span>
<span class="co1">// &#31867;&#27169;&#26495; basic_&shy;string_&shy;view</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits <span class="sy1">=</span> char_traits<span class="sy1">&lt;</span>CharT<span class="sy1">&gt;&gt;</span>
<span class="kw1">class</span> basic_string_view<span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits<span class="sy1">&gt;</span>
<span class="kw1">inline</span> <span class="kw4">constexpr</span> <span class="kw4">bool</span> ranges<span class="sy4">::</span><span class="me2">enable_view</span><span class="sy1">&lt;</span>basic_string_view<span class="sy1">&lt;</span>CharT, Traits<span class="sy1">&gt;&gt;</span> <span class="sy1">=</span> <span class="kw2">true</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits<span class="sy1">&gt;</span>
<span class="kw1">inline</span> <span class="kw4">constexpr</span> <span class="kw4">bool</span> ranges<span class="sy4">::</span><span class="me2">enable_borrowed_range</span><span class="sy1">&lt;</span>basic_string_view<span class="sy1">&lt;</span>CharT, Traits<span class="sy1">&gt;&gt;</span> <span class="sy1">=</span>
<span class="kw2">true</span><span class="sy4">;</span>
<span class="co1">// &#38750;&#25104;&#21592;&#20989;&#25968;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits<span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> operator<span class="sy1">==</span><span class="br0">(</span>basic_string_view<span class="sy1">&lt;</span>CharT, Traits<span class="sy1">&gt;</span> x,
basic_string_view<span class="sy1">&lt;</span>CharT, Traits<span class="sy1">&gt;</span> y<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits<span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> <span class="coMULTI">/* &#35265;&#25551;&#36848; */</span>
operator<span class="sy1">&lt;=&gt;</span><span class="br0">(</span>basic_string_view<span class="sy1">&lt;</span>CharT, Traits<span class="sy1">&gt;</span> x,
basic_string_view<span class="sy1">&lt;</span>CharT, Traits<span class="sy1">&gt;</span> y<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="co1">// &#20805;&#36275;&#30340;&#27604;&#36739;&#20989;&#25968;&#39069;&#22806;&#37325;&#36733;</span>
<span class="co1">// &#25554;&#20837;&#22120;&#19982;&#25552;&#21462;&#22120;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits<span class="sy1">&gt;</span>
basic_ostream<span class="sy1">&lt;</span>CharT, Traits<span class="sy1">&gt;</span><span class="sy3">&amp;</span>
operator<span class="sy1">&lt;&lt;</span><span class="br0">(</span>basic_ostream<span class="sy1">&lt;</span>CharT, Traits<span class="sy1">&gt;</span><span class="sy3">&amp;</span> os,
basic_string_view<span class="sy1">&lt;</span>CharT, Traits<span class="sy1">&gt;</span> str<span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// basic_&shy;string_&shy;view typedef &#21517;</span>
<span class="kw1">using</span> string_view <span class="sy1">=</span> basic_string_view<span class="sy1">&lt;</span><span class="kw4">char</span><span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">using</span> u8string_view <span class="sy1">=</span> basic_string_view<span class="sy1">&lt;</span>char8_t<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">using</span> u16string_view <span class="sy1">=</span> basic_string_view<span class="sy1">&lt;</span><span class="kw4">char16_t</span><span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">using</span> u32string_view <span class="sy1">=</span> basic_string_view<span class="sy1">&lt;</span><span class="kw4">char32_t</span><span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">using</span> wstring_view <span class="sy1">=</span> basic_string_view<span class="sy1">&lt;</span><span class="kw4">wchar_t</span><span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="co1">// &#25955;&#21015;&#25903;&#25345;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> T<span class="sy1">&gt;</span> <span class="kw1">struct</span> hash<span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;&gt;</span> <span class="kw1">struct</span> hash<span class="sy1">&lt;</span>string_view<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;&gt;</span> <span class="kw1">struct</span> hash<span class="sy1">&lt;</span>u8string_view<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;&gt;</span> <span class="kw1">struct</span> hash<span class="sy1">&lt;</span>u16string_view<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;&gt;</span> <span class="kw1">struct</span> hash<span class="sy1">&lt;</span>u32string_view<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;&gt;</span> <span class="kw1">struct</span> hash<span class="sy1">&lt;</span>wstring_view<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">inline</span> <span class="kw1">namespace</span> literals <span class="br0">{</span>
<span class="kw1">inline</span> <span class="kw1">namespace</span> string_view_literals <span class="br0">{</span>
<span class="co1">// basic_&shy;string_&shy;view &#23383;&#38754;&#37327;&#30340;&#21518;&#32512;</span>
<span class="kw4">constexpr</span> string_view operator<span class="st0">&quot;&quot;</span>sv<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char</span><span class="sy2">*</span> str, size_t len<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> u8string_view operator<span class="st0">&quot;&quot;</span>sv<span class="br0">(</span><span class="kw4">const</span> char8_t<span class="sy2">*</span> str, size_t len<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> u16string_view operator<span class="st0">&quot;&quot;</span>sv<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char16_t</span><span class="sy2">*</span> str, size_t len<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> u32string_view operator<span class="st0">&quot;&quot;</span>sv<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char32_t</span><span class="sy2">*</span> str, size_t len<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> wstring_view operator<span class="st0">&quot;&quot;</span>sv<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">wchar_t</span><span class="sy2">*</span> str, size_t len<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="br0">}</span>
<span class="br0">}</span></pre></div>
</div>
<h4><span class="mw-headline" id=".E7.B1.BB.E6.A8.A1.E6.9D.BF_std::basic_string_view">&#31867;&#27169;&#26495; <span class="t-lc"><a href="cpp-string-basic_string_view.html">std::basic_string_view</a></span></span></h4>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="cpp source-cpp">
<pre class="de1"><span class="kw1">namespace</span> std <span class="br0">{</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits <span class="sy1">=</span> char_traits<span class="sy1">&lt;</span>CharT<span class="sy1">&gt;&gt;</span>
<span class="kw1">class</span> basic_string_view <span class="br0">{</span>
<span class="kw1">public</span><span class="sy4">:</span>
<span class="co1">// &#31867;&#22411;</span>
<span class="kw1">using</span> Traits_type <span class="sy1">=</span> Traits<span class="sy4">;</span>
<span class="kw1">using</span> value_type <span class="sy1">=</span> CharT<span class="sy4">;</span>
<span class="kw1">using</span> pointer <span class="sy1">=</span> value_type<span class="sy2">*</span><span class="sy4">;</span>
<span class="kw1">using</span> const_pointer <span class="sy1">=</span> <span class="kw4">const</span> value_type<span class="sy2">*</span><span class="sy4">;</span>
<span class="kw1">using</span> reference <span class="sy1">=</span> value_type<span class="sy3">&amp;</span><span class="sy4">;</span>
<span class="kw1">using</span> const_reference <span class="sy1">=</span> <span class="kw4">const</span> value_type<span class="sy3">&amp;</span><span class="sy4">;</span>
<span class="kw1">using</span> const_iterator <span class="sy1">=</span> <span class="coMULTI">/* &#30001;&#23454;&#29616;&#23450;&#20041; */</span>
<span class="kw1">using</span> iterator <span class="sy1">=</span> const_iterator<span class="sy4">;</span>
<span class="kw1">using</span> const_reverse_iterator <span class="sy1">=</span> reverse_iterator<span class="sy1">&lt;</span>const_iterator<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw1">using</span> reverse_iterator <span class="sy1">=</span> const_reverse_iterator<span class="sy4">;</span>
<span class="kw1">using</span> size_type <span class="sy1">=</span> size_t<span class="sy4">;</span>
<span class="kw1">using</span> difference_type <span class="sy1">=</span> ptrdiff_t<span class="sy4">;</span>
<span class="kw4">static</span> <span class="kw4">constexpr</span> size_type npos <span class="sy1">=</span> size_type<span class="br0">(</span><span class="sy2">-</span><span class="nu0">1</span><span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// &#26500;&#36896;&#19982;&#36171;&#20540;</span>
<span class="kw4">constexpr</span> basic_string_view<span class="br0">(</span><span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> basic_string_view<span class="br0">(</span><span class="kw4">const</span> basic_string_view<span class="sy3">&amp;</span><span class="br0">)</span> <span class="kw1">noexcept</span> <span class="sy1">=</span> <span class="kw1">default</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> basic_string_view<span class="sy3">&amp;</span> operator<span class="sy1">=</span><span class="br0">(</span><span class="kw4">const</span> basic_string_view<span class="sy3">&amp;</span><span class="br0">)</span> <span class="kw1">noexcept</span> <span class="sy1">=</span> <span class="kw1">default</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> basic_string_view<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> str<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> basic_string_view<span class="br0">(</span>nullptr_t<span class="br0">)</span> <span class="sy1">=</span> delete<span class="sy4">;</span>
<span class="kw4">constexpr</span> basic_string_view<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> str, size_type len<span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> It, <span class="kw1">class</span> End<span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> basic_string_view<span class="br0">(</span>It begin, End end<span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> R<span class="sy1">&gt;</span>
<span class="kw4">constexpr</span> basic_string_view<span class="br0">(</span>R<span class="sy3">&amp;&amp;</span> r<span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// &#36845;&#20195;&#22120;&#25903;&#25345;</span>
<span class="kw4">constexpr</span> const_iterator begin<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_iterator end<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_iterator cbegin<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_iterator cend<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_reverse_iterator rbegin<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_reverse_iterator rend<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_reverse_iterator crbegin<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_reverse_iterator crend<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="co1">// &#23481;&#37327;</span>
<span class="kw4">constexpr</span> size_type size<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type length<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type max_size<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="br0">[</span><span class="br0">[</span>nodiscard<span class="br0">]</span><span class="br0">]</span> <span class="kw4">constexpr</span> <span class="kw4">bool</span> empty<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="co1">// &#20803;&#32032;&#35775;&#38382;</span>
<span class="kw4">constexpr</span> const_reference operator<span class="br0">[</span><span class="br0">]</span><span class="br0">(</span>size_type pos<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_reference at<span class="br0">(</span>size_type pos<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_reference front<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_reference back<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> const_pointer data<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="co1">// &#20462;&#25913;&#22120;</span>
<span class="kw4">constexpr</span> <span class="kw4">void</span> remove_prefix<span class="br0">(</span>size_type n<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">void</span> remove_suffix<span class="br0">(</span>size_type n<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">void</span> swap<span class="br0">(</span>basic_string_view<span class="sy3">&amp;</span> s<span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="co1">// &#23383;&#31526;&#20018;&#25805;&#20316;</span>
<span class="kw4">constexpr</span> size_type copy<span class="br0">(</span>CharT<span class="sy2">*</span> s, size_type n, size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> basic_string_view substr<span class="br0">(</span>size_type pos <span class="sy1">=</span> <span class="nu0">0</span>, size_type n <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">int</span> compare<span class="br0">(</span>basic_string_view s<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">int</span> compare<span class="br0">(</span>size_type pos1, size_type n1, basic_string_view s<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">int</span> compare<span class="br0">(</span>size_type pos1, size_type n1, basic_string_view s,
size_type pos2, size_type n2<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">int</span> compare<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">int</span> compare<span class="br0">(</span>size_type pos1, size_type n1, <span class="kw4">const</span> CharT<span class="sy2">*</span> s<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">int</span> compare<span class="br0">(</span>size_type pos1, size_type n1, <span class="kw4">const</span> CharT<span class="sy2">*</span> s,
size_type n2<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> starts_with<span class="br0">(</span>basic_string_view x<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> starts_with<span class="br0">(</span>CharT x<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> starts_with<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> x<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> ends_with<span class="br0">(</span>basic_string_view x<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> ends_with<span class="br0">(</span>CharT x<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> ends_with<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> x<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> contains<span class="br0">(</span>basic_string_view x<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> contains<span class="br0">(</span>CharT x<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> <span class="kw4">bool</span> contains<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> x<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="co1">// &#25628;&#32034;</span>
<span class="kw4">constexpr</span> size_type find<span class="br0">(</span>basic_string_view s, size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find<span class="br0">(</span>CharT c, size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos, size_type n<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type rfind<span class="br0">(</span>basic_string_view s, size_type pos <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type rfind<span class="br0">(</span>CharT c, size_type pos <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type rfind<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos, size_type n<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type rfind<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_first_of<span class="br0">(</span>basic_string_view s,
size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_first_of<span class="br0">(</span>CharT c, size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_first_of<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos, size_type n<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_first_of<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_last_of<span class="br0">(</span>basic_string_view s,
size_type pos <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_last_of<span class="br0">(</span>CharT c, size_type pos <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_last_of<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos, size_type n<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_last_of<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_first_not_of<span class="br0">(</span>basic_string_view s,
size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_first_not_of<span class="br0">(</span>CharT c, size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_first_not_of<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos,
size_type n<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_first_not_of<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos <span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_last_not_of<span class="br0">(</span>basic_string_view s,
size_type pos <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_last_not_of<span class="br0">(</span>CharT c, size_type pos <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span> <span class="kw1">noexcept</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_last_not_of<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos,
size_type n<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw4">constexpr</span> size_type find_last_not_of<span class="br0">(</span><span class="kw4">const</span> CharT<span class="sy2">*</span> s, size_type pos <span class="sy1">=</span> npos<span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw1">private</span><span class="sy4">:</span>
const_pointer data_<span class="sy4">;</span> <span class="co1">// &#20165;&#29992;&#20110;&#38416;&#37322;</span>
size_type size_<span class="sy4">;</span> <span class="co1">// &#20165;&#29992;&#20110;&#38416;&#37322;</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="co1">// &#25512;&#23548;&#25351;&#24341;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> It, <span class="kw1">class</span> End<span class="sy1">&gt;</span>
basic_string_view<span class="br0">(</span>It, End<span class="br0">)</span> <span class="sy2">-</span><span class="sy1">&gt;</span> basic_string_view<span class="sy1">&lt;</span>iter_value_t<span class="sy1">&lt;</span>It<span class="sy1">&gt;&gt;</span><span class="sy4">;</span>
<span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> R<span class="sy1">&gt;</span>
basic_string_view<span class="br0">(</span>R<span class="sy3">&amp;&amp;</span><span class="br0">)</span> <span class="sy2">-</span><span class="sy1">&gt;</span> basic_string_view<span class="sy1">&lt;</span>ranges<span class="sy4">::</span><span class="me2">range_value_t</span><span class="sy1">&lt;</span>R<span class="sy1">&gt;&gt;</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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