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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::basic_istream&lt;CharT,Traits&gt;::</span>get</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_istream.html">basic istream</a></span></div>
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<div><span class="mw-geshi cpp source-cpp">int_type get<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></span></div>
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<div><span class="mw-geshi cpp source-cpp">basic_istream<span class="sy3">&amp;</span> get<span class="br0">(</span> char_type<span class="sy3">&amp;</span> ch <span class="br0">)</span><span class="sy4">;</span></span></div>
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<div><span class="mw-geshi cpp source-cpp">basic_istream<span class="sy3">&amp;</span> get<span class="br0">(</span> char_type<span class="sy2">*</span> s, <a href="cpp-io-streamsize.html"><span class="kw1804">std::<span class="me2">streamsize</span></span></a> count <span class="br0">)</span><span class="sy4">;</span></span></div>
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<div><span class="mw-geshi cpp source-cpp">basic_istream<span class="sy3">&amp;</span> get<span class="br0">(</span> char_type<span class="sy2">*</span> s, <a href="cpp-io-streamsize.html"><span class="kw1804">std::<span class="me2">streamsize</span></span></a> count, char_type delim <span class="br0">)</span><span class="sy4">;</span></span></div>
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<div><span class="mw-geshi cpp source-cpp">basic_istream<span class="sy3">&amp;</span> get<span class="br0">(</span> basic_streambuf<span class="sy3">&amp;</span> strbuf <span class="br0">)</span><span class="sy4">;</span></span></div>
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<div><span class="mw-geshi cpp source-cpp">basic_istream<span class="sy3">&amp;</span> get<span class="br0">(</span> basic_streambuf<span class="sy3">&amp;</span> strbuf, char_type delim <span class="br0">)</span><span class="sy4">;</span></span></div>
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<p>&#20174;&#27969;&#37322;&#20986;&#23383;&#31526;&#25110;&#22810;&#20010;&#23383;&#31526;&#12290;</p>
<p>&#25152;&#26377;&#29256;&#26412;&#37117;&#34920;&#29616;&#20026;<a href="cpp-named_req-UnformattedInputFunction.html"><span style="font-style:italic">&#26080;&#26684;&#24335;&#36755;&#20837;&#20989;&#25968;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(UnformattedInputFunction)</span></a> &#12290;&#26500;&#36896;&#24182;&#26816;&#26597; sentry &#23545;&#35937;&#21518;&#65292;&#36825;&#20123;&#20989;&#25968;&#36827;&#34892;&#19979;&#21015;&#20869;&#23481;&#65306;</p>
<div class="t-li1"><span class="t-li">1)</span> &#35835;&#21462;&#19968;&#20010;&#23383;&#31526;&#65292;&#33509;&#21487;&#29992;&#21017;&#36820;&#22238;&#23427;&#12290;&#21542;&#21017;&#65292;&#36820;&#22238; <span class="t-c"><span class="mw-geshi cpp source-cpp">Traits<span class="sy4">::</span><span class="me2">eof</span><span class="br0">(</span><span class="br0">)</span></span></span> &#24182;&#35774;&#32622; <span class="t-lc"><a href="cpp-io-ios_base-iostate.html">failbit</a></span> &#21644; <span class="t-lc"><a href="cpp-io-ios_base-iostate.html">eofbit</a></span> &#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> &#35835;&#21462;&#19968;&#20010;&#23383;&#31526;&#65292;&#32780;&#33509;&#21487;&#29992;&#21017;&#23384;&#20648;&#20110; <code>ch</code> &#12290;&#21542;&#21017;&#65292;&#20445;&#30041; <code>ch</code> &#19981;&#20462;&#25913;&#24182;&#35774;&#32622; <span class="t-lc"><a href="cpp-io-ios_base-iostate.html">failbit</a></span> &#21644; <span class="t-lc"><a href="cpp-io-ios_base-iostate.html">eofbit</a></span> &#12290;&#27880;&#24847;&#27492;&#20989;&#25968;&#19981;&#22312;&#31867;&#22411; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">signed</span> <span class="kw4">char</span></span></span> &#21644; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">unsigned</span> <span class="kw4">char</span></span></span> &#37325;&#36733;&#65292;&#19981;&#21516;&#20110;&#26377;&#26684;&#24335;&#23383;&#31526;&#36755;&#20837; operator&gt;&gt; &#12290;</div>
<div class="t-li1"><span class="t-li">3)</span> &#21516; <span class="t-c"><span class="mw-geshi cpp source-cpp">get<span class="br0">(</span>s, count, widen<span class="br0">(</span><span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="br0">)</span><span class="br0">)</span></span></span> &#65292;&#21363;&#35835;&#21462;&#33267;&#22810; <span class="t-c"><span class="mw-geshi cpp source-cpp">count<span class="sy2">-</span><span class="nu0">1</span></span></span> &#20010;&#23383;&#31526;&#24182;&#23384;&#20648;&#23427;&#20204;&#21040; <code>s</code> &#25152;&#25351;&#21521;&#30340;&#23383;&#31526;&#20018;&#20013;&#65292;&#30452;&#33267;&#25214;&#21040; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&#39;<span class="es1">\n</span>&#39;</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">4)</span> &#35835;&#21462;&#23383;&#31526;&#24182;&#23384;&#20648;&#23427;&#20204;&#21040;&#39318;&#20803;&#32032;&#20026; <code>s</code> &#25152;&#25351;&#21521;&#30340;&#23383;&#31526;&#25968;&#32452;&#30340;&#30456;&#32487;&#20301;&#32622;&#12290;&#37322;&#20986;&#24182;&#23384;&#20648;&#23383;&#31526;&#65292;&#30452;&#33267;&#20986;&#29616;&#20219;&#20309;&#19979;&#21015;&#26465;&#20214;&#65306;</div>
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<li>&#24050;&#23384;&#20648; <span class="t-c"><span class="mw-geshi cpp source-cpp">count <span class="sy2">-</span> <span class="nu0">1</span></span></span> &#20010;&#23383;&#31526;</li>
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<ul>
<li>&#36755;&#20837;&#24207;&#21015;&#20013;&#20986;&#29616;&#25991;&#20214;&#23614;&#26465;&#20214;&#65288;&#35843;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">setstate<span class="br0">(</span>eofbit<span class="br0">)</span></span></span> &#65289;</li>
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<li>&#19979;&#20010;&#21487;&#29992;&#36755;&#20837;&#23383;&#31526; <code>c</code> &#31561;&#20110; <code>delim</code> &#65292;&#20197; <span class="t-c"><span class="mw-geshi cpp source-cpp">Traits<span class="sy4">::</span><span class="me2">eq</span><span class="br0">(</span>c, delim<span class="br0">)</span></span></span> &#30830;&#23450;&#12290;&#19981;&#37322;&#20986;&#27492;&#23383;&#31526;&#65288;&#19981;&#21516;&#20110; <span class="t-lc"><a href="cpp-io-basic_istream-getline.html">basic_istream::getline()</a></span> &#65289;&#12290;</li>
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<div class="t-li1"><span class="t-li"></span> &#33509;&#26410;&#37322;&#20986;&#23383;&#31526;&#65292;&#21017;&#35843;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">setstate<span class="br0">(</span>failbit<span class="br0">)</span></span></span> &#12290;&#20219;&#20309;&#24773;&#20917;&#19979;&#65292;&#33509; <code>count&gt;0</code> &#65292;&#21017;&#23384;&#20648;&#31354;&#23383;&#31526;&#65288; <span class="t-c"><span class="mw-geshi cpp source-cpp">CharT<span class="br0">(</span><span class="br0">)</span></span></span> &#65289;&#20110;&#25968;&#32452;&#30340;&#19979;&#20010;&#30456;&#32487;&#20301;&#32622;&#12290;</div>
<div class="t-li1"><span class="t-li">5)</span> &#21516; <span class="t-c"><span class="mw-geshi cpp source-cpp">get<span class="br0">(</span>strbuf, widen<span class="br0">(</span><span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="br0">)</span><span class="br0">)</span></span></span> &#65292;&#21363;&#35835;&#21462;&#21487;&#29992;&#23383;&#31526;&#24182;&#25554;&#20837;&#23427;&#20204;&#21040;&#32473;&#23450;&#30340; <a href="cpp-io-basic_streambuf.html"><tt>basic_streambuf</tt></a> &#23545;&#35937;&#65292;&#30452;&#33267;&#25214;&#21040; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="st0">&#39;<span class="es1">\n</span>&#39;</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">6)</span> &#35835;&#21462;&#23383;&#31526;&#24182;&#25554;&#20837;&#23427;&#20204;&#21040;&#32473;&#23450;&#30340; <a href="cpp-io-basic_streambuf.html"><tt>basic_streambuf</tt></a> &#23545;&#35937;&#25152;&#25511;&#21046;&#30340;&#36755;&#20986;&#24207;&#21015;&#12290;&#37322;&#20986;&#24182;&#25554;&#20837;&#23383;&#31526;&#21040; <code>strbuf</code> &#20013;&#65292;&#30452;&#33267;&#20986;&#29616;&#20219;&#20309;&#19979;&#21015;&#26465;&#20214;&#65306;</div>
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<li>&#36755;&#20837;&#24207;&#21015;&#20013;&#20986;&#29616;&#25991;&#20214;&#23614;&#26465;&#20214;</li>
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<li>&#25554;&#20837;&#36755;&#20986;&#24207;&#21015;&#22833;&#36133;&#65288;&#35813;&#24773;&#20917;&#19979;&#19981;&#37322;&#20986;&#26080;&#27861;&#25554;&#20837;&#30340;&#23383;&#31526;&#65289;</li>
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<li>&#19979;&#20010;&#21487;&#29992;&#36755;&#20837;&#23383;&#31526; <code>c</code> &#31561;&#20110; <code>delim</code> &#65292;&#20197; <span class="t-c"><span class="mw-geshi cpp source-cpp">Traits<span class="sy4">::</span><span class="me2">eq</span><span class="br0">(</span>c, delim<span class="br0">)</span></span></span> &#30830;&#23450;&#12290;&#19981;&#37322;&#20986;&#27492;&#23383;&#31526;&#12290;</li>
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<dd>
<dl>
<dd>
<ul>
<li>&#20986;&#29616;&#24322;&#24120;&#65288;&#35813;&#24773;&#20917;&#19979;&#25429;&#33719;&#32780;&#19981;&#37325;&#25243;&#24322;&#24120;&#65289;&#12290;</li>
</ul>
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<div class="t-li1"><span class="t-li"></span> &#33509;&#26410;&#37322;&#20986;&#23383;&#31526;&#65292;&#21017;&#35843;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">setstate<span class="br0">(</span>failbit<span class="br0">)</span></span></span> &#12290;</div>
<p>&#25152;&#26377;&#29256;&#26412;&#37117;&#35774;&#32622; <span class="t-lc"><a href="cpp-io-basic_istream-gcount.html">gcount()</a></span> &#30340;&#20540;&#20026;&#37322;&#20986;&#30340;&#23383;&#31526;&#25968;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
<table class="t-par-begin">
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<td>ch</td>
<td>-</td>
<td>&#21040;&#35201;&#20889;&#20837;&#32467;&#26524;&#21040;&#30340;&#23383;&#31526;&#30340;&#24341;&#29992;</td>
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<tr class="t-par">
<td>s</td>
<td>-</td>
<td>&#25351;&#21521;&#35201;&#23384;&#20648;&#32467;&#26524;&#21040;&#30340;&#23383;&#31526;&#20018;&#30340;&#25351;&#38024;</td>
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<td>count</td>
<td>-</td>
<td><code>s</code> &#25152;&#25351;&#21521;&#30340;&#23383;&#31526;&#20018;&#30340;&#22823;&#23567;</td>
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<td>delim</td>
<td>-</td>
<td>&#29992;&#20197;&#20572;&#27490;&#37322;&#20986;&#30340;&#20998;&#38548;&#23383;&#31526;&#12290;&#19981;&#37322;&#20986;&#19988;&#19981;&#23384;&#20648;&#23427;&#12290;</td>
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<td>strbuf</td>
<td>-</td>
<td>&#35201;&#35835;&#21462;&#20869;&#23481;&#21040;&#30340;&#27969;&#32531;&#20914;</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>
<div class="t-li1"><span class="t-li">1)</span> &#37322;&#20986;&#30340;&#23383;&#31526;&#25110; <span class="t-c"><span class="mw-geshi cpp source-cpp">Traits<span class="sy4">::</span><span class="me2">eof</span><span class="br0">(</span><span class="br0">)</span></span></span></div>
<div class="t-li1"><span class="t-li">2-6)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span></div>
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">&#24322;&#24120;</span></h3>
<div class="t-template-editlink" style=""></div>
&#33509;&#20986;&#29616;&#38169;&#35823;&#65288;&#38169;&#35823;&#29366;&#24577;&#26631;&#24535;&#19981;&#26159; <span class="t-lc"><a href="cpp-io-ios_base-iostate.html">goodbit</a></span> &#65289;&#24182;&#19988;&#35774;&#32622;&#20102; <span class="t-lc"><a href="cpp-io-basic_ios-exceptions.html">exceptions()</a></span> &#20026;&#23545;&#35813;&#29366;&#24577;&#25243;&#20986;&#21017;&#20026; <span class="t-lc"><a href="cpp-io-ios_base-failure.html">failure</a></span> &#12290;
<p>&#33509;&#20869;&#37096;&#25805;&#20316;&#25243;&#20986;&#24322;&#24120;&#65292;&#21017;&#25429;&#33719;&#23427;&#24182;&#35774;&#32622; <span class="t-lc"><a href="cpp-io-ios_base-iostate.html">badbit</a></span> &#12290;&#33509;&#23545; <code>badbit</code> &#35774;&#32622;&#20102; <span class="t-lc"><a href="cpp-io-basic_ios-exceptions.html">exceptions()</a></span> &#65292;&#21017;&#37325;&#25243;&#35813;&#24322;&#24120;&#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>
<a href="cpp-io-basic_istringstream.html"><span class="kw1735">std::<span class="me2">istringstream</span></span></a> s1<span class="br0">(</span><span class="st0">&quot;Hello, world.&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">char</span> c1 <span class="sy1">=</span> s1.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#35835;&#21462;&#39;H&#39;</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 &quot;</span> <span class="sy1">&lt;&lt;</span> c1 <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;, gcount() == &quot;</span> <span class="sy1">&lt;&lt;</span> s1.<span class="me1">gcount</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="kw4">char</span> c2<span class="sy4">;</span>
s1.<span class="me1">get</span><span class="br0">(</span>c2<span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#35835;&#21462; &#39;e&#39;</span>
<span class="kw4">char</span> str<span class="br0">[</span><span class="nu0">5</span><span class="br0">]</span><span class="sy4">;</span>
s1.<span class="me1">get</span><span class="br0">(</span>str, <span class="nu0">5</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#35835;&#21462; &quot;llo,&quot;</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 &quot;</span> <span class="sy1">&lt;&lt;</span> str <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;, gcount() == &quot;</span> <span class="sy1">&lt;&lt;</span> s1.<span class="me1">gcount</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</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> c1 <span class="sy1">&lt;&lt;</span> c2 <span class="sy1">&lt;&lt;</span> str<span class="sy4">;</span>
s1.<span class="me1">get</span><span class="br0">(</span><span class="sy2">*</span><a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a>.<span class="me1">rdbuf</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#35835;&#21462;&#21097;&#20313;&#65292;&#19981;&#21253;&#25324; &#39;\n&#39;</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;<span class="es1">\n</span>After the last get(), gcount() == &quot;</span> <span class="sy1">&lt;&lt;</span> s1.<span class="me1">gcount</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
</div>
<p>&#36755;&#20986;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="text source-text">
<pre class="de1">after reading H, gcount() == 1
after reading llo,, gcount() == 4
Hello, world.
After the last get(), gcount() == 7</pre></div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
<table class="t-dsc-begin">
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-io-basic_istream-read.html"><span class="t-lines"><span>read</span></span></a></div>
</div>
</td>
<td>&#35835;&#24182;&#21462;&#36208;&#19968;&#22359;&#23383;&#31526;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-io-basic_istream-operator_gtgt.html"><span class="t-lines"><span>operator&gt;&gt;</span></span></a></div>
</div>
</td>
<td>&#25552;&#21462;&#24102;&#26684;&#24335;&#25968;&#25454;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-io-basic_istream-operator_gtgt2.html"><span class="t-lines"><span>operator&gt;&gt;<span class="t-dsc-small">(std::basic_istream)</span></span></span></a></div>
</div>
</td>
<td>&#25552;&#21462;&#23383;&#31526;&#21644;&#23383;&#31526;&#25968;&#32452;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
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