klarkxy/hustoj
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
196e706fe41f737f31d8617ead8fe566aa616329
hustoj/web/cppreference-zh/chmhelp/c-string-byte-tolower.html
klarkxy 196e706fe4 上传cppreference
2025-08-01 12:57:54 +08:00

155 lines
8.6 KiB
HTML
Raw Blame History

<!DOCTYPE html>
<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
<head><meta http-equiv="x-ua-compatible" content="ie=edge">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>tolower</title>
<link rel="stylesheet" href="ext.css" />
<link rel="stylesheet" href="site_modules.css" />
</head>
<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-c_string_byte_tolower skin-cppreference2 action-view cpp-navbar">
<div id="cpp-content-base">
<div id="content"><a id="top"></a>
<h1 id="firstHeading" class="firstHeading">tolower</h1>
<div id="bodyContent">
<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>
<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
<table class="t-dcl-begin">
<tbody>
<tr class="t-dsc-header">
<td>
<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code>&lt;ctype.h&gt;</code></div>
</td>
<td></td>
<td></td>
</tr>
<tr class="t-dcl">
<td class="t-dcl-nopad">
<div><span class="mw-geshi c source-c"><span class="kw4">int</span> tolower<span class="br0">(</span> <span class="kw4">int</span> ch <span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td class="t-dcl-nopad"></td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl-sep">
<td></td>
<td></td>
<td></td>
</tr>
</tbody>
</table>
<p>&#25353;&#29031;&#24403;&#21069;&#23433;&#35013;&#30340; C &#26412;&#22320;&#29615;&#22659;&#25152;&#23450;&#20041;&#30340;&#35268;&#21017;&#65292;&#36716;&#25442;&#32473;&#23450;&#23383;&#31526;&#20026;&#23567;&#20889;&#12290;</p>
<p>&#40664;&#35748; <code>&quot;C&quot;</code> &#26412;&#22320;&#29615;&#22659;&#20013;&#65292;&#20197;&#20998;&#21035;&#23567;&#20889;&#23383;&#27597; <code>ABCDEFGHIJKLMNOPQRSTUVWXYZ</code> &#26367;&#25442;&#22823;&#20889;&#23383;&#27597; <code>abcdefghijklmnopqrstuvwxyz</code> &#12290;</p>
<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>ch</td>
<td>-</td>
<td>&#35201;&#36716;&#25442;&#30340;&#23383;&#31526;&#12290;&#33509; <code>ch</code> &#30340;&#20540;&#19981;&#33021;&#34920;&#31034;&#20026; <span class="t-c"><span class="mw-geshi c source-c"><span class="kw4">unsigned</span> <span class="kw4">char</span></span></span> &#19988;&#19981;&#31561;&#20110; <span class="t-c"><span class="mw-geshi c source-c"><a href="c-io.html"><span class="kw888">EOF</span></a></span></span> &#65292;&#21017;&#34892;&#20026;&#26410;&#23450;&#20041;&#12290;</td>
</tr>
</table>
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p><code>ch</code> &#30340;&#23567;&#20889;&#29256;&#26412;&#65292;&#25110;&#33509;&#24403;&#21069; C &#26412;&#22320;&#29615;&#22659;&#20013;&#26080;&#23567;&#20889;&#29256;&#26412;&#65292;&#21017;&#36820;&#22238;&#19981;&#20462;&#25913;&#30340; <code>ch</code> &#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="c source-c">
<pre class="de1"><span class="co2">#include &lt;stdio.h&gt;</span>
<span class="co2">#include &lt;ctype.h&gt;</span>
<span class="co2">#include &lt;locale.h&gt;</span>
<span class="co2">#include &lt;limits.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="coMULTI">/* &#22312;&#40664;&#35748;&#26412;&#22320;&#29615;&#22659;&#65306; */</span>
<span class="kw4">unsigned</span> <span class="kw4">char</span> l<span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">unsigned</span> <span class="kw4">char</span> u<span class="sy1">=</span><span class="nu0">0</span><span class="sy4">;</span> u<span class="sy1">&lt;</span><a href="c-types-limits.html"><span class="kw367">UCHAR_MAX</span></a><span class="sy4">;</span> u<span class="sy2">++</span><span class="br0">)</span> <span class="br0">{</span>
l <span class="sy1">=</span> tolower<span class="br0">(</span>u<span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">if</span> <span class="br0">(</span>l<span class="sy3">!</span><span class="sy1">=</span>u<span class="br0">)</span> <a href="c-io-fprintf.html"><span class="kw850">printf</span></a><span class="br0">(</span><span class="st0">&quot;%c%c &quot;</span>, u,l<span class="br0">)</span><span class="sy4">;</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;<span class="es1">\n</span><span class="es1">\n</span>&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">unsigned</span> <span class="kw4">char</span> c <span class="sy1">=</span> <span class="st0">&#39;<span class="es2">\xb4</span>&#39;</span><span class="sy4">;</span> <span class="co1">// ISO-8859-15 &#30340;&#23383;&#31526; &#381;</span>
<span class="co1">// &#20294;&#22312; ISO-8859-1&#20026; &acute; &#65288;&#38160;&#38899;&#31526;&#65289;</span>
<span class="kw4">unsigned</span> <span class="kw4">char</span> c2 <span class="sy1">=</span> c<span class="sy4">;</span> <span class="co1">// &#20026;&#25171;&#21360;</span>
<a href="c-locale-setlocale.html"><span class="kw900">setlocale</span></a><span class="br0">(</span><a href="c-locale-LC_categories.html"><span class="kw903">LC_ALL</span></a>, <span class="st0">&quot;en_US.iso88591&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw850">printf</span></a><span class="br0">(</span><span class="st0">&quot;in iso8859-1, tolower(&#39;0x%x&#39;) gives 0x%x<span class="es1">\n</span>&quot;</span>, c2, tolower<span class="br0">(</span>c<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-locale-setlocale.html"><span class="kw900">setlocale</span></a><span class="br0">(</span><a href="c-locale-LC_categories.html"><span class="kw903">LC_ALL</span></a>, <span class="st0">&quot;en_US.iso885915&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw850">printf</span></a><span class="br0">(</span><span class="st0">&quot;in iso8859-15, tolower(&#39;0x%x&#39;) gives 0x%x<span class="es1">\n</span>&quot;</span>, c2, tolower<span class="br0">(</span>c<span class="br0">)</span><span class="br0">)</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">Aa Bb Cc Dd Ee Ff Gg Hh Ii Jj Kk Ll Mm Nn Oo Pp Qq Rr Ss Tt Uu Vv Ww Xx Yy Zz
in iso8859-1, tolower(&#39;0xb4&#39;) gives 0xb4
in iso8859-15, tolower(&#39;0xb4&#39;) gives 0xb8</pre></div>
</div>
</div>
<h3><span class="mw-headline" id=".E5.BC.95.E7.94.A8">&#24341;&#29992;</span></h3>
<div class="t-ref-std-11">
<ul>
<li>C11 &#26631;&#20934;&#65288;ISO/IEC 9899:2011&#65289;&#65306;</li>
</ul>
<dl>
<dd>
<ul>
<li>7.4.2.1 The tolower function (p: 203)</li>
</ul>
</dd>
</dl>
<div class="t-ref-std-c99">
<ul>
<li>C99 &#26631;&#20934;&#65288;ISO/IEC 9899:1999&#65289;&#65306;</li>
</ul>
<dl>
<dd>
<ul>
<li>7.4.2.1 The tolower function (p: 184)</li>
</ul>
</dd>
</dl>
<div class="t-ref-std-c89">
<ul>
<li>C89/C90 &#26631;&#20934;&#65288;ISO/IEC 9899:1990&#65289;&#65306;</li>
</ul>
<dl>
<dd>
<ul>
<li>4.3.2.1 The tolower function</li>
</ul>
</dd>
</dl>
</div>
<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="c-string-byte-toupper.html"><span class="t-lines"><span>toupper</span></span></a></div>
</div>
</td>
<td>&#23558;&#23383;&#31526;&#36716;&#25442;&#25104;&#22823;&#20889;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="c-string-wide-towlower.html"><span class="t-lines"><span>towlower</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-c95">(C95)</span></span></span></div>
</div>
</td>
<td>&#23558;&#23485;&#23383;&#31526;&#36716;&#25442;&#20026;&#23567;&#20889;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
</tr>
</table>
</div>
</div>
</div>
<div class="visualClear"></div>
</div>
</div>
</div>
</body>
</html>
Reference in New Issue View Git Blame Copy Permalink