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<title>std::regex_traits&lt;CharT&gt;::value</title>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::regex_traits&lt;CharT&gt;::</span>value</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-regex.html">regex</a>&lrm; | <a href="cpp-regex-regex_traits.html">regex traits</a></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">int</span> value<span class="br0">(</span> CharT ch, <span class="kw4">int</span> radix <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-since-cxx11">(C++11 &#36215;)</span></td>
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<p>&#32473;&#23450;&#24403;&#21069;&#24863;&#26579;&#30340;&#26412;&#22320;&#29615;&#22659;&#65292;&#30830;&#23450;&#25968;&#20301; <code>ch</code> &#22312;&#25968;&#20540;&#24213; <code>radix</code> &#20013;&#34920;&#31034;&#30340;&#20540;&#12290; <span class="t-lc"><a href="cpp-regex-basic_regex.html">std::regex</a></span> &#22312;&#22788;&#29702;&#22914; <code>{1</code>} &#25110; <code>{2,5</code>} &#30340;<a href="cpp-regex-ecmascript.html#.E6.95.B0.E9.87.8F.E8.AF.8D">&#25968;&#37327;&#35789;</a>&#12289;&#22914; <code>\1</code> &#30340;<a href="cpp-regex-ecmascript.html#.E5.9B.9E.E6.BA.AF.E5.BC.95.E7.94.A8">&#22238;&#28335;&#24341;&#29992;</a>&#21644;&#21313;&#20845;&#36827;&#21046;&#21450; Unicode &#23383;&#31526;&#36716;&#20041;&#26102;&#35843;&#29992;&#27492;&#20989;&#25968;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>ch</td>
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<td>&#21487;&#20197;&#34920;&#31034;&#25968;&#20301;&#30340;&#23383;&#31526;</td>
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<td>radix</td>
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<td>8 &#12289; 10 &#25110; 16 &#20043;&#19968;</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>&#33509; <code>ch</code> &#22312;&#24403;&#21069;&#24863;&#26579;&#30340;&#26412;&#22320;&#29615;&#22659;&#20013;&#30830;&#23454;&#34920;&#31034;&#23545;&#20110;&#25968;&#20540;&#24213; <code>radix</code> &#21512;&#27861;&#30340;&#25968;&#20301;&#65292;&#21017;&#20026;&#20854;&#25968;&#20540;&#65292;&#38169;&#35823;&#26102;&#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">-</span><span class="nu0">1</span></span></span> &#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;iostream&gt;</span>
<span class="co2">#include &lt;locale&gt;</span>
<span class="co2">#include &lt;regex&gt;</span>
<span class="co2">#include &lt;map&gt;</span>
<span class="co1">// &#27492;&#23450;&#21046;&#27491;&#21017;&#34920;&#36798;&#24335;&#29305;&#24615;&#20801;&#35768;&#26085;&#25991;&#25968;&#23383;</span>
<span class="kw1">struct</span> jnum_traits <span class="sy4">:</span> <a href="cpp-regex-regex_traits.html"><span class="kw2026">std::<span class="me2">regex_traits</span></span></a><span class="sy1">&lt;</span><span class="kw4">wchar_t</span><span class="sy1">&gt;</span>
<span class="br0">{</span>
<span class="kw4">static</span> <a href="cpp-container-map.html"><span class="kw1281">std::<span class="me2">map</span></span></a><span class="sy1">&lt;</span><span class="kw4">wchar_t</span>, <span class="kw4">int</span><span class="sy1">&gt;</span> data<span class="sy4">;</span>
<span class="kw4">int</span> value<span class="br0">(</span><span class="kw4">wchar_t</span> ch, <span class="kw4">int</span> radix <span class="br0">)</span> <span class="kw4">const</span> <span class="br0">{</span>
<span class="kw4">wchar_t</span> up <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">toupper</span><span class="br0">(</span>ch, getloc<span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">return</span> data.<span class="me1">count</span><span class="br0">(</span>up<span class="br0">)</span> <span class="sy4">?</span> data<span class="br0">[</span>up<span class="br0">]</span> <span class="sy4">:</span> regex_traits<span class="sy4">::</span><span class="me2">value</span><span class="br0">(</span>ch, radix<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="br0">}</span><span class="sy4">;</span>
<a href="cpp-container-map.html"><span class="kw1281">std::<span class="me2">map</span></span></a><span class="sy1">&lt;</span><span class="kw4">wchar_t</span>, <span class="kw4">int</span><span class="sy1">&gt;</span> jnum_traits<span class="sy4">::</span><span class="me2">data</span> <span class="sy1">=</span> <span class="br0">{</span><span class="br0">{</span>L<span class="st0">&#39;&#12295;&#39;</span>,<span class="nu0">0</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#19968;&#39;</span>,<span class="nu0">1</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#20108;&#39;</span>,<span class="nu0">2</span><span class="br0">}</span>,
<span class="br0">{</span>L<span class="st0">&#39;&#19977;&#39;</span>,<span class="nu0">3</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#22235;&#39;</span>,<span class="nu0">4</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#20116;&#39;</span>,<span class="nu0">5</span><span class="br0">}</span>,
<span class="br0">{</span>L<span class="st0">&#39;&#20845;&#39;</span>,<span class="nu0">6</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#19971;&#39;</span>,<span class="nu0">7</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#20843;&#39;</span>,<span class="nu0">8</span><span class="br0">}</span>,
<span class="br0">{</span>L<span class="st0">&#39;&#20061;&#39;</span>,<span class="nu0">9</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#65313;&#39;</span>,<span class="nu0">10</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#65314;&#39;</span>,<span class="nu0">11</span><span class="br0">}</span>,
<span class="br0">{</span>L<span class="st0">&#39;&#65315;&#39;</span>,<span class="nu0">12</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#65316;&#39;</span>,<span class="nu0">13</span><span class="br0">}</span>, <span class="br0">{</span>L<span class="st0">&#39;&#65317;&#39;</span>,<span class="nu0">14</span><span class="br0">}</span>,
<span class="br0">{</span>L<span class="st0">&#39;&#65318;&#39;</span>,<span class="nu0">15</span><span class="br0">}</span><span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
std<span class="sy4">::</span><span class="me2">locale</span><span class="sy4">::</span><span class="me2">global</span><span class="br0">(</span><a href="cpp-locale-locale.html"><span class="kw1894">std::<span class="me2">locale</span></span></a><span class="br0">(</span><span class="st0">&quot;ja_JP.utf8&quot;</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1759">std::<span class="me2">wcout</span></span></a>.<span class="me1">sync_with_stdio</span><span class="br0">(</span><span class="kw2">false</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1759">std::<span class="me2">wcout</span></span></a>.<span class="me1">imbue</span><span class="br0">(</span><a href="cpp-locale-locale.html"><span class="kw1894">std::<span class="me2">locale</span></span></a><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-string-basic_string.html"><span class="kw1232">std::<span class="me2">wstring</span></span></a> in <span class="sy1">=</span> L<span class="st0">&quot;&#39080;&quot;</span><span class="sy4">;</span>
<span class="kw1">if</span><span class="br0">(</span><a href="cpp-regex-regex_match.html"><span class="kw2012">std::<span class="me2">regex_match</span></span></a><span class="br0">(</span>in, <a href="cpp-regex-basic_regex.html"><span class="kw2001">std::<span class="me2">wregex</span></span></a><span class="br0">(</span>L<span class="st0">&quot;<span class="es1">\\</span>u98a8&quot;</span><span class="br0">)</span><span class="br0">)</span><span class="br0">)</span>
<a href="cpp-io-cout.html"><span class="kw1759">std::<span class="me2">wcout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;<span class="es1">\\</span>u98a8 matched &quot;</span> <span class="sy1">&lt;&lt;</span> in <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="kw1">if</span><span class="br0">(</span><a href="cpp-regex-regex_match.html"><span class="kw2012">std::<span class="me2">regex_match</span></span></a><span class="br0">(</span>in, <a href="cpp-regex-basic_regex.html"><span class="kw1999">std::<span class="me2">basic_regex</span></span></a><span class="sy1">&lt;</span><span class="kw4">wchar_t</span>, jnum_traits<span class="sy1">&gt;</span><span class="br0">(</span>L<span class="st0">&quot;<span class="es1">\\</span>u&#20061;&#20843;&#65345;&#20843;&quot;</span><span class="br0">)</span><span class="br0">)</span><span class="br0">)</span>
<a href="cpp-io-cout.html"><span class="kw1759">std::<span class="me2">wcout</span></span></a> <span class="sy1">&lt;&lt;</span> L<span class="st0">&quot;<span class="es1">\\</span>u&#20061;&#20843;&#65345;&#20843; with custom traits matched &quot;</span> <span class="sy1">&lt;&lt;</span> in <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">\u98a8 matched &#39080;
\u&#20061;&#20843;&#65345;&#20843; with custom traits matched &#39080;</pre></div>
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