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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::strstreambuf::</span>pcount</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-strstreambuf.html">strstreambuf</a></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">int</span> pcount<span class="br0">(</span><span class="br0">)</span> <span class="kw4">const</span><span class="sy4">;</span></span></div>
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<p>&#36820;&#22238;&#20889;&#20837;&#36755;&#20986;&#24207;&#21015;&#30340;&#23383;&#31526;&#25968;&#12290;</p>
<p>&#33509;&#25918;&#32622;&#21306;&#30340;&#19979;&#19968;&#20301;&#32622;&#25351;&#38024;&#65288; <span class="t-lc"><a href="cpp-io-basic_streambuf-pptr.html">std::streambuf::pptr()</a></span> &#65289;&#20026;&#31354;&#25351;&#38024;&#65292;&#21017;&#36820;&#22238;&#38646;&#12290;</p>
<p>&#21542;&#21017;&#65292;&#36820;&#22238;&#25918;&#32622;&#21306;&#20013;&#30340;&#19979;&#19968;&#20301;&#32622;&#25351;&#38024;&#20943;&#25918;&#32622;&#21306;&#20013;&#30340;&#36215;&#22987;&#25351;&#38024;&#65292;&#21363; <span class="t-c"><span class="mw-geshi cpp source-cpp">pptr<span class="br0">(</span><span class="br0">)</span> <span class="sy2">-</span> pbase<span class="br0">(</span><span class="br0">)</span></span></span> &#12290;</p>
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<p>&#65288;&#26080;&#65289;</p>
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p>&#20889;&#20837;&#25918;&#32622;&#21306;&#30340;&#23383;&#31526;&#25968;&#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;strstream&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-strstream.html"><span class="kw1755">std::<span class="me2">strstream</span></span></a> dyn<span class="sy4">;</span> <span class="co1">// &#21160;&#24577;&#20998;&#37197;&#30340;&#36755;&#20986;&#32531;&#20914;&#21306;</span>
dyn <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;Test: &quot;</span> <span class="sy1">&lt;&lt;</span> <span class="nu16">1.23</span> <span class="sy1">&lt;&lt;</span> <a href="cpp-io-manip-ends.html"><span class="kw1789">std::<span class="me2">ends</span></span></a><span class="sy4">;</span>
<a href="cpp-io-strstreambuf.html"><span class="kw1752">std::<span class="me2">strstreambuf</span></span></a><span class="sy2">*</span> buf <span class="sy1">=</span> dyn.<span class="me1">rdbuf</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;The size of the output is &quot;</span>
<span class="sy1">&lt;&lt;</span> buf<span class="sy2">-</span><span class="sy1">&gt;</span>pcount<span class="br0">(</span><span class="br0">)</span> <span class="co1">// or just buf.pcount()</span>
<span class="sy1">&lt;&lt;</span> <span class="st0">&quot; and it holds <span class="es1">\&quot;</span>&quot;</span> <span class="sy1">&lt;&lt;</span> dyn.<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>
dyn.<span class="me1">freeze</span><span class="br0">(</span><span class="kw2">false</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#22312;&#21160;&#24577;&#27969;&#19978;&#35843;&#29992; .str() &#21518;</span>
<span class="kw4">char</span> arr<span class="br0">[</span><span class="nu0">10</span><span class="br0">]</span><span class="sy4">;</span>
<a href="cpp-io-ostrstream.html"><span class="kw1754">std::<span class="me2">ostrstream</span></span></a> user<span class="br0">(</span>arr, <span class="nu0">10</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#29992;&#25143;&#25552;&#20379;&#30340;&#36755;&#20986;&#32531;&#20914;&#21306;</span>
buf <span class="sy1">=</span> user.<span class="me1">rdbuf</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
user <span class="sy1">&lt;&lt;</span> <span class="nu16">1.23</span><span class="sy4">;</span> <span class="co1">// &#27880;&#24847;&#65306;&#26080; std::ends</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a>.<span class="me1">write</span><span class="br0">(</span>arr, buf<span class="sy2">-</span><span class="sy1">&gt;</span>pcount<span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#25110;&#23601;&#26159; user.pcount()</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">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<a href="cpp-io-istrstream.html"><span class="kw1753">std::<span class="me2">istrstream</span></span></a> lit<span class="br0">(</span><span class="st0">&quot;1 2 3&quot;</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#21482;&#35835;&#22266;&#23450;&#22823;&#23567;&#32531;&#20914;&#21306;</span>
buf <span class="sy1">=</span> lit.<span class="me1">rdbuf</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// istrstream &#26080;&#25104;&#21592; pcount() &#65292;&#25925; lit.pcount() &#23558;&#19981;&#24037;&#20316;</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;Input-only pcount() = &quot;</span> <span class="sy1">&lt;&lt;</span> buf<span class="sy2">-</span><span class="sy1">&gt;</span>pcount<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>
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<p>&#36755;&#20986;&#65306;</p>
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<pre class="de1">The size of the output is 11 and it holds &quot;Test: 1.23&quot;
1.23
Input-only pcount() = 0</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-strstream-pcount.html"><span class="t-lines"><span>pcount</span></span></a></div>
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<td>&#33719;&#24471;&#20889;&#20837;&#30340;&#23383;&#31526;&#25968;<br />
<span class="t-mark">(<code>std::strstream</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-io-ostrstream-pcount.html"><span class="t-lines"><span>pcount</span></span></a></div>
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<td>&#33719;&#24471;&#20889;&#20837;&#30340;&#23383;&#31526;&#25968;<br />
<span class="t-mark">(<code>std::ostrstream</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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