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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::basic_stringbuf&lt;CharT,Traits,Allocator&gt;::</span>str</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-io.html">io</a>&lrm; | <a href="cpp-io-basic_stringbuf.html">basic stringbuf</a></span></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="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1">&lt;</span>CharT, Traits, Allocator<span class="sy1">&gt;</span> str<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<td><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"><a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1">&lt;</span>CharT, Traits, Allocator<span class="sy1">&gt;</span> str<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy3">&amp;</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
<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="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> SAlloc<span class="sy1">&gt;</span><br />
<a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1">&lt;</span>CharT, Traits, Allocator<span class="sy1">&gt;</span> str<span class="br0">(</span> <span class="kw4">const</span> SAlloc<span class="sy3">&amp;</span> a <span class="br0">)</span> <span class="kw4">const</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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<div><span class="mw-geshi cpp source-cpp"><a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1">&lt;</span>CharT, Traits, Allocator<span class="sy1">&gt;</span> str<span class="br0">(</span><span class="br0">)</span> <span class="sy3">&amp;&amp;</span><span class="sy4">;</span></span></div>
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<td>(3)</td>
<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">void</span> str<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1">&lt;</span>CharT, Traits, Allocator<span class="sy1">&gt;</span><span class="sy3">&amp;</span> s <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(4)</td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span><span class="kw1">class</span> SAlloc<span class="sy1">&gt;</span><br />
<span class="kw4">void</span> str<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1">&lt;</span>CharT, Traits, SAlloc<span class="sy1">&gt;</span><span class="sy3">&amp;</span> s <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(5)</td>
<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">void</span> str<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">&lt;</span>CharT, Traits, Allocator<span class="sy1">&gt;</span><span class="sy3">&amp;&amp;</span> s <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td>(6)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
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<p>&#33719;&#21462;&#21644;&#35774;&#32622;&#24213;&#23618;&#23383;&#31526;&#20018;&#12290;</p>
<p>&#20026;&#35299;&#37322;&#30446;&#30340;&#65292;&#20196; <code>buf_</code> &#20195;&#34920;&#20445;&#26377;&#24213;&#23618;&#23383;&#31526;&#24207;&#21015;&#30340;&#20869;&#37096; <span class="t-lc"><a href="cpp-string-basic_string.html">std::basic_string</a></span> &#23545;&#35937;&#12290;&#23450;&#20041;<i>&#32531;&#20914;&#25351;&#38024;&#21021;&#22987;&#21270;</i>&#22914;&#19979;&#65306;</p>
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<li>&#23545;&#20110;&#36755;&#20837;&#27969;&#65288; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">bool</span><span class="br0">(</span>mode <span class="sy3">&amp;</span> <a href="cpp-io-ios_base-openmode.html"><span class="kw1674">std::<span class="me2">ios_base</span><span class="sy4">::</span><span class="me2">in</span></span></a><span class="br0">)</span> <span class="sy1">==</span> <span class="kw2">true</span></span></span> &#65289;&#65292;&#20351; <span class="t-c"><span class="mw-geshi cpp source-cpp">eback<span class="br0">(</span><span class="br0">)</span></span></span> &#25351;&#21521;&#39318;&#23383;&#31526;&#65292; <span class="t-c"><span class="mw-geshi cpp source-cpp">gptr<span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> eback<span class="br0">(</span><span class="br0">)</span></span></span> &#65292;&#32780; <span class="t-c"><span class="mw-geshi cpp source-cpp">egptr<span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> eback<span class="br0">(</span><span class="br0">)</span> <span class="sy2">+</span> buf_.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span></span></span> &#65306;&#21518;&#32487;&#36755;&#20837;&#23558;&#35835;&#21462;&#39318;&#20010;&#23383;&#31526;&#20018;&#30340;&#23383;&#31526;&#12290;</li>
<li>&#23545;&#20110;&#36755;&#20986;&#27969;&#65288; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">bool</span><span class="br0">(</span>mode <span class="sy3">&amp;</span> <a href="cpp-io-ios_base-openmode.html"><span class="kw1675">std::<span class="me2">ios_base</span><span class="sy4">::</span><span class="me2">out</span></span></a><span class="br0">)</span> <span class="sy1">==</span> <span class="kw2">true</span></span></span> &#65289;&#65292;&#20351; <span class="t-c"><span class="mw-geshi cpp source-cpp">pbase<span class="br0">(</span><span class="br0">)</span></span></span> &#25351;&#21521;&#39318;&#23383;&#31526;&#32780; <span class="t-c"><span class="mw-geshi cpp source-cpp">epptr<span class="br0">(</span><span class="br0">)</span> <span class="sy1">&gt;=</span> pbase<span class="br0">(</span><span class="br0">)</span> <span class="sy2">+</span> buf_.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span></span></span> &#65288;&#20801;&#35768; <code>epptr()</code> &#25351;&#21521;&#26356;&#21518;&#65292;&#20197;&#20196;&#21518;&#38543;&#30340; <code>sputc()</code> &#19981;&#20250;&#31435;&#21363;&#35843;&#29992; <code>overflow()</code> &#65289;</li>
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<li>&#23545;&#20110;&#21518;&#38468;&#27969;&#65288; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">bool</span><span class="br0">(</span>mode <span class="sy3">&amp;</span> <a href="cpp-io-ios_base-openmode.html"><span class="kw1677">std::<span class="me2">ios_base</span><span class="sy4">::</span><span class="me2">ate</span></span></a><span class="br0">)</span> <span class="sy1">==</span> <span class="kw2">true</span></span></span> &#65289;&#65292;&#20351; <span class="t-c"><span class="mw-geshi cpp source-cpp">pptr<span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> pbase<span class="br0">(</span><span class="br0">)</span> <span class="sy2">+</span> buf_.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span></span></span> &#65292;&#20174;&#32780;&#21518;&#32487;&#36755;&#20986;&#23558;&#34987;&#21518;&#38468;&#21040;&#23383;&#31526;&#20018;&#30340;&#26368;&#21518;&#23383;&#31526;&#12290;</li>
</ul>
</dd>
</dl>
</td>
<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<ul>
<li>&#23545;&#20110;&#38750;&#21518;&#38468;&#36755;&#20986;&#27969;&#65292;&#20351; <span class="t-c"><span class="mw-geshi cpp source-cpp">pptr<span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> pbase<span class="br0">(</span><span class="br0">)</span></span></span> &#65292;&#20174;&#32780;&#21518;&#32487;&#36755;&#20986;&#23558;&#37325;&#20889;&#23383;&#31526;&#20018;&#30340;&#23383;&#31526;&#12290;</li>
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<div class="t-li1"><span class="t-li">1)</span> &#21019;&#24314;&#24182;&#36820;&#22238;&#20445;&#26377;&#27492; <code>std::basic_stringbuf</code> &#24213;&#23618;&#23383;&#31526;&#24207;&#21015;&#21103;&#26412;&#30340; <span class="t-lc"><a href="cpp-string-basic_string.html">std::basic_string</a></span> &#12290;&#23545;&#20110;&#20165;&#36755;&#20837;&#27969;&#65292;&#36820;&#22238;&#30340;&#23383;&#31526;&#20018;&#21547;&#26469;&#33258;&#33539;&#22260; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="br0">[</span>eback<span class="br0">(</span><span class="br0">)</span>, egptr<span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span> &#30340;&#23383;&#31526;&#12290;&#23545;&#20110;&#36755;&#20837;/&#36755;&#20986;&#25110;&#20165;&#36755;&#20986;&#27969;&#65292;&#21547;&#26377; <span class="t-c"><span class="mw-geshi cpp source-cpp">pbase<span class="br0">(</span><span class="br0">)</span></span></span> &#21040;&#24207;&#21015;&#20013;&#26411;&#23383;&#31526;&#30340;&#23383;&#31526;&#65292;&#19981;&#32771;&#34385; <span class="t-c"><span class="mw-geshi cpp source-cpp">egptr<span class="br0">(</span><span class="br0">)</span></span></span> &#21644; <span class="t-c"><span class="mw-geshi cpp source-cpp">epptr<span class="br0">(</span><span class="br0">)</span></span></span> &#12290;
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<p>&#20026;&#20889;&#20837;&#25171;&#24320;&#30340;&#32531;&#20914;&#21306;&#20013;&#30340;&#25104;&#21592;&#23383;&#31526;&#24207;&#21015;&#33021;&#20026;&#25928;&#29575;&#30446;&#30340;&#36807;&#20998;&#37197;&#12290;&#35813;&#24773;&#20917;&#19979;&#65292;&#20165;&#36820;&#22238;<i>&#21021;&#22987;&#21270;&#30340;&#23383;&#31526;</i>&#65306;&#20174;&#26500;&#36896;&#20989;&#25968; string &#21442;&#25968;&#33719;&#24471;&#30340;&#23383;&#31526;&#12289;&#26368;&#36817;&#23545; <code>str()</code> &#30340;&#35774;&#32622;&#22120;&#37325;&#36733;&#30340; string &#21442;&#25968;&#30340;&#23383;&#31526;&#25110;&#26469;&#33258;&#20889;&#20837;&#25805;&#20316;&#30340;&#23383;&#31526;&#12290;&#20856;&#22411;&#30340;&#20351;&#29992;&#36807;&#20998;&#37197;&#30340;&#23454;&#29616;&#32500;&#25252;&#19968;&#20010;&#39640;&#27700;&#20301;&#25351;&#38024;&#65292;&#20197;&#36319;&#36394;&#32531;&#20914;&#21306;&#24050;&#21021;&#22987;&#21270;&#37096;&#20998;&#30340;&#32467;&#23614;&#65292;&#32780;&#27492;&#37325;&#36733;&#36820;&#22238;&#20174; <span class="t-c"><span class="mw-geshi cpp source-cpp">pbase<span class="br0">(</span><span class="br0">)</span></span></span> &#21040;&#39640;&#27700;&#20301;&#25351;&#38024;&#30340;&#23383;&#31526;&#12290;</p>
</td>
<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<p>&#31561;&#20215;&#20110; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1">&lt;</span>CharT, Traits, Allocator<span class="sy1">&gt;</span><span class="br0">(</span>view<span class="br0">(</span><span class="br0">)</span>, get_allocator<span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span></span></span> &#12290;</p>
</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
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<div class="t-li1"><span class="t-li">2)</span> &#21516; <span class="t-v">(1)</span> &#65292;&#38500;&#20102;&#29992; <code>a</code> &#26500;&#36896;&#36820;&#22238;&#30340; <code>std::basic_string</code> &#12290;&#31561;&#20215;&#20110; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1">&lt;</span>CharT, Traits, SAlloc<span class="sy1">&gt;</span><span class="br0">(</span>view<span class="br0">(</span><span class="br0">)</span>, a<span class="br0">)</span><span class="sy4">;</span></span></span> &#12290;&#27492;&#37325;&#36733;&#20165;&#33509; <code>SAlloc</code> &#28385;&#36275;<a href="cpp-named_req-Allocator.html"><span style="font-style:italic">&#20998;&#37197;&#22120;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(Allocator)</span></a> &#30340;&#35201;&#27714;&#25165;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;</div>
<div class="t-li1"><span class="t-li">3)</span> &#21019;&#24314; <span class="t-lc"><a href="cpp-string-basic_string.html">std::basic_string</a></span> &#23545;&#35937;&#65292;&#22914;&#21516;&#20197; <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span>buf_<span class="br0">)</span></span></span> &#21021;&#22987;&#21270;&#12290;&#21487;&#33021;&#38656;&#35201;&#39318;&#20808;&#35843;&#33410; <code>buf_</code> &#20197;&#20351;&#20043;&#21547;&#26377;&#21516; <span class="t-v">(1)</span> &#30340;&#20869;&#23481;&#12290;&#26500;&#36896;&#35813; <code>std::basic_string</code> &#23545;&#35937;&#21518;&#65292;&#35774;&#32622; <code>buf_</code> &#20026;&#31354;&#24182;&#36827;&#34892;&#32531;&#20914;&#25351;&#38024;&#21021;&#22987;&#21270;&#65292;&#28982;&#21518;&#36820;&#22238; <code>std::basic_string</code> &#23545;&#35937;&#12290;</div>
<div class="t-li1"><span class="t-li">4)</span> &#22914;&#21516;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">buf_ <span class="sy1">=</span> s</span></span> &#26367;&#25442;&#24213;&#23618;&#23383;&#31526;&#24207;&#21015;&#65292;&#28982;&#21518;&#36827;&#34892;&#32531;&#20914;&#25351;&#38024;&#21021;&#22987;&#21270;&#12290;</div>
<div class="t-li1"><span class="t-li">5)</span> &#21516; <span class="t-v">(4)</span> &#65292;&#38500;&#20102; <code>s</code> &#30340;&#20998;&#37197;&#22120;&#30340;&#31867;&#22411;&#19981;&#26159; <code>Allocator</code> &#12290;&#27492;&#37325;&#36733;&#20165;&#33509; <code>SAlloc</code> &#19982; <code>Allocator</code> &#19981;&#26159;&#21516;&#19968;&#31867;&#22411;&#25165;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;</div>
<div class="t-li1"><span class="t-li">6)</span> &#22914;&#21516;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">buf_ <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span>s<span class="br0">)</span></span></span> &#26367;&#25442;&#24213;&#23618;&#23383;&#31526;&#24207;&#21015;&#65292;&#28982;&#21518;&#36827;&#34892;&#32531;&#20914;&#25351;&#38024;&#21021;&#22987;&#21270;&#12290;</div>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
<table class="t-par-begin">
<tr class="t-par">
<td>s</td>
<td>-</td>
<td>&#20445;&#26377;&#26367;&#25442;&#23383;&#31526;&#24207;&#21015;&#30340; <code>basic_string</code> &#23545;&#35937;</td>
</tr>
<tr class="t-par">
<td>a</td>
<td>-</td>
<td>&#36820;&#22238;&#30340; <code>basic_string</code> &#30340;&#25152;&#26377;&#20869;&#23384;&#20998;&#37197;&#25152;&#29992;&#30340;&#20998;&#37197;&#22120;</td>
</tr>
</table>
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<div class="t-li1"><span class="t-li">1-3)</span> &#20445;&#26377;&#27492;&#32531;&#20914;&#30340;&#24213;&#23618;&#23383;&#31526;&#24207;&#21015;&#30340; <code>basic_string</code> &#23545;&#35937;&#12290;</div>
<div class="t-li1"><span class="t-li">4-6)</span> &#65288;&#26080;&#65289;</div>
<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">&#27880;&#35299;</span></h3>
<p>&#24120;&#36890;&#36807; <span class="t-lc"><a href="cpp-io-basic_istringstream-str.html">std::basic_istringstream::str()</a></span> &#12289; <span class="t-lc"><a href="cpp-io-basic_ostringstream-str.html">std::basic_ostringstream::str()</a></span> &#25110; <span class="t-lc"><a href="cpp-io-basic_stringstream-str.html">std::basic_stringstream::str()</a></span> &#35775;&#38382;&#27492;&#20989;&#25968;&#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</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 &lt;sstream&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="kw4">int</span> n<span class="sy4">;</span>
<a href="cpp-io-basic_istringstream.html"><span class="kw1735">std::<span class="me2">istringstream</span></span></a> in<span class="sy4">;</span> <span class="co1">// &#20134;&#33021;&#29992; in(&quot;1 2&quot;)</span>
in.<span class="me1">rdbuf</span><span class="br0">(</span><span class="br0">)</span><span class="sy2">-</span><span class="sy1">&gt;</span>str<span class="br0">(</span><span class="st0">&quot;1 2&quot;</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#35774;&#32622;&#33719;&#21462;&#21306;</span>
in <span class="sy1">&gt;&gt;</span> n<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;after reading the first int from <span class="es1">\&quot;</span>1 2<span class="es1">\&quot;</span>, the int is &quot;</span>
<span class="sy1">&lt;&lt;</span> n <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;, str() = <span class="es1">\&quot;</span>&quot;</span> <span class="sy1">&lt;&lt;</span> in.<span class="me1">rdbuf</span><span class="br0">(</span><span class="br0">)</span><span class="sy2">-</span><span class="sy1">&gt;</span>str<span class="br0">(</span><span class="br0">)</span> <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="co1">// &#25110; in.str()</span>
<a href="cpp-io-basic_ostringstream.html"><span class="kw1736">std::<span class="me2">ostringstream</span></span></a> out<span class="br0">(</span><span class="st0">&quot;1 2&quot;</span><span class="br0">)</span><span class="sy4">;</span>
out <span class="sy1">&lt;&lt;</span> <span class="nu0">3</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;after writing the int &#39;3&#39; to output stream <span class="es1">\&quot;</span>1 2<span class="es1">\&quot;</span>&quot;</span>
<span class="sy1">&lt;&lt;</span> <span class="st0">&quot;, str() = <span class="es1">\&quot;</span>&quot;</span> <span class="sy1">&lt;&lt;</span> out.<span class="me1">str</span><span class="br0">(</span><span class="br0">)</span> <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-basic_ostringstream.html"><span class="kw1736">std::<span class="me2">ostringstream</span></span></a> ate<span class="br0">(</span><span class="st0">&quot;1 2&quot;</span>, <a href="cpp-io-ios_base-openmode.html"><span class="kw1677">std::<span class="me2">ios_base</span><span class="sy4">::</span><span class="me2">ate</span></span></a><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// C++11</span>
ate <span class="sy1">&lt;&lt;</span> <span class="nu0">3</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;after writing the int &#39;3&#39; to append stream <span class="es1">\&quot;</span>1 2<span class="es1">\&quot;</span>&quot;</span>
<span class="sy1">&lt;&lt;</span> <span class="st0">&quot;, str() = <span class="es1">\&quot;</span>&quot;</span> <span class="sy1">&lt;&lt;</span> ate.<span class="me1">str</span><span class="br0">(</span><span class="br0">)</span> <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>&#36755;&#20986;&#65306;</p>
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<pre class="de1">after reading the first int from &quot;1 2&quot;, the int is 1, str() = &quot;1 2&quot;
after writing the int &#39;3&#39; to output stream &quot;1 2&quot;, str() = &quot;3 2&quot;
after writing the int &#39;3&#39; to append stream &quot;1 2&quot;, str() = &quot;1 23&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-io-basic_stringstream-str.html"><span class="t-lines"><span>str</span></span></a></div>
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<td>&#33719;&#21462;&#25110;&#35774;&#32622;&#24213;&#23618;&#23383;&#31526;&#20018;&#35774;&#22791;&#23545;&#35937;&#30340;&#20869;&#23481;<br />
<span class="t-mark">(<code>std::basic_stringstream&lt;CharT,Traits,Allocator&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-io-basic_stringbuf-view.html"><span class="t-lines"><span>view</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
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<td>&#33719;&#24471;&#24213;&#23618;&#23383;&#31526;&#24207;&#21015;&#19978;&#30340;&#35270;&#22270;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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