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<div id="contentSub"><span class="subpages">&lt; <a href="c.html">c</a>&lrm; | <a href="c-string.html">string</a>&lrm; | <a href="c-string-byte.html">byte</a></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code>&lt;string.h&gt;</code></div>
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<div><span class="mw-geshi c source-c"><span class="kw4">char</span> <span class="sy2">*</span>strchr<span class="br0">(</span> <span class="kw4">const</span> <span class="kw4">char</span> <span class="sy2">*</span>str, <span class="kw4">int</span> ch <span class="br0">)</span><span class="sy4">;</span></span></div>
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<p>&#23547;&#25214; <code>ch</code> &#65288;&#22914;&#21516;&#29992; <span class="t-c"><span class="mw-geshi c source-c"><span class="br0">(</span><span class="kw4">char</span><span class="br0">)</span>ch</span></span> &#36716;&#25442;&#25104; <span class="t-c"><span class="mw-geshi c source-c"><span class="kw4">char</span></span></span> &#21518;&#65289;&#22312; <code>str</code> &#25152;&#25351;&#21521;&#30340;&#31354;&#32456;&#27490;&#23383;&#33410;&#23383;&#31526;&#20018;&#65288;&#36716;&#35793;&#27599;&#20010;&#23383;&#31526;&#20026; <span class="t-c"><span class="mw-geshi c source-c"><span class="kw4">unsigned</span> <span class="kw4">char</span></span></span> &#65289;&#20013;&#30340;&#39318;&#27425;&#20986;&#29616;&#20301;&#32622;&#12290;&#32456;&#27490;&#31354;&#23383;&#31526;&#34987;&#35748;&#20026;&#26159;&#23383;&#31526;&#20018;&#30340;&#19968;&#37096;&#20998;&#65292;&#24182;&#19988;&#33021;&#22312;&#23547;&#25214; <span class="t-c"><span class="mw-geshi c source-c"><span class="st0">&#39;<span class="es5">\0</span>&#39;</span></span></span> &#26102;&#25214;&#21040;&#12290;</p>
<p>&#33509; <code>str</code> &#19981;&#26159;&#25351;&#21521;&#31354;&#32456;&#27490;&#23383;&#33410;&#23383;&#31526;&#20018;&#30340;&#25351;&#38024;&#65292;&#21017;&#34892;&#20026;&#26410;&#23450;&#20041;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>str</td>
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<td>&#25351;&#21521;&#24453;&#20998;&#26512;&#30340;&#31354;&#32456;&#27490;&#23383;&#33410;&#23383;&#31526;&#20018;&#30340;&#25351;&#38024;</td>
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<td>ch</td>
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<td>&#35201;&#25628;&#32034;&#30340;&#23383;&#31526;</td>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p>&#25351;&#21521; <code>str</code> &#25214;&#21040;&#30340;&#23383;&#31526;&#30340;&#25351;&#38024;&#65292;&#33509;&#26410;&#25214;&#21040;&#35813;&#23383;&#31526;&#21017;&#20026;&#31354;&#25351;&#38024;&#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;stdio.h&gt;</span>
<span class="co2">#include &lt;string.h&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="kw4">void</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="kw4">const</span> <span class="kw4">char</span> <span class="sy2">*</span>str <span class="sy1">=</span> <span class="st0">&quot;Try not. Do, or do not. There is no try.&quot;</span><span class="sy4">;</span>
<span class="kw4">char</span> target <span class="sy1">=</span> <span class="st0">&#39;T&#39;</span><span class="sy4">;</span>
<span class="kw4">const</span> <span class="kw4">char</span> <span class="sy2">*</span>result <span class="sy1">=</span> str<span class="sy4">;</span>
<span class="kw1">while</span><span class="br0">(</span><span class="br0">(</span>result <span class="sy1">=</span> strchr<span class="br0">(</span>result, target<span class="br0">)</span><span class="br0">)</span> <span class="sy3">!</span><span class="sy1">=</span> <a href="c-types-NULL.html"><span class="kw103">NULL</span></a><span class="br0">)</span> <span class="br0">{</span>
<a href="c-io-fprintf.html"><span class="kw850">printf</span></a><span class="br0">(</span><span class="st0">&quot;Found &#39;%c&#39; starting at &#39;%s&#39;<span class="es1">\n</span>&quot;</span>, target, result<span class="br0">)</span><span class="sy4">;</span>
<span class="sy2">++</span>result<span class="sy4">;</span> <span class="co1">// result &#33258;&#22686;&#65292;&#21542;&#21017;&#25105;&#20204;&#20250;&#25214;&#21040;&#30456;&#21516;&#20301;&#32622;&#30340;&#30446;&#26631;</span>
<span class="br0">}</span>
<span class="br0">}</span></pre></div>
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<p>&#36755;&#20986;&#65306;</p>
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<pre class="de1">Found &#39;T&#39; starting at &#39;Try not. Do, or do not. There is no try.&#39;
Found &#39;T&#39; starting at &#39;There is no try.&#39;</pre></div>
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<h3><span class="mw-headline" id=".E5.BC.95.E7.94.A8">&#24341;&#29992;</span></h3>
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<li>C11 &#26631;&#20934;&#65288;ISO/IEC 9899:2011&#65289;&#65306;</li>
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<li>7.24.5.2 The strchr function (p: 367-368)</li>
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<li>C99 &#26631;&#20934;&#65288;ISO/IEC 9899:1999&#65289;&#65306;</li>
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<li>7.21.5.2 The strchr function (p: 330)</li>
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<li>C89/C90 &#26631;&#20934;&#65288;ISO/IEC 9899:1990&#65289;&#65306;</li>
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<li>4.11.5.2 The strchr function</li>
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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="c-string-byte-memchr.html"><span class="t-lines"><span>memchr</span></span></a></div>
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<td>&#22312;&#25968;&#32452;&#20013;&#25628;&#32034;&#23383;&#31526;&#30340;&#39318;&#27425;&#20986;&#29616;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<div><a href="c-string-byte-strrchr.html"><span class="t-lines"><span>strrchr</span></span></a></div>
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<td>&#26597;&#25214;&#23383;&#31526;&#30340;&#26368;&#21518;&#19968;&#27425;&#20986;&#29616;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<div><a href="c-string-byte-strpbrk.html"><span class="t-lines"><span>strpbrk</span></span></a></div>
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<td>&#26597;&#25214;&#19968;&#20010;&#23383;&#31526;&#20018;&#20013;&#30340;&#20219;&#24847;&#19968;&#20010;&#23383;&#31526;&#22312;&#21478;&#19968;&#20010;&#23383;&#31526;&#20018;&#20013;&#30340;&#39318;&#20010;&#20301;&#32622;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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