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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>use_facet</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-locale.html">locale</a></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-locale.html">&lt;locale&gt;</a></code></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Facet <span class="sy1">&gt;</span><br />
<span class="kw4">const</span> Facet<span class="sy3">&amp;</span> use_facet<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-locale-locale.html"><span class="kw1894">std::<span class="me2">locale</span></span></a><span class="sy3">&amp;</span> loc <span class="br0">)</span><span class="sy4">;</span></span></div>
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<p>&#33719;&#24471;&#21040; <code>loc</code> &#25152;&#23454;&#35013;&#30340;&#24179;&#38754;&#30340;&#24341;&#29992;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>loc</td>
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<td>&#35201;&#26597;&#35810;&#30340; locale &#23545;&#35937;</td>
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<p>&#36820;&#22238;&#21040;&#24179;&#38754;&#30340;&#24341;&#29992;&#65292;&#21482;&#35201;&#23384;&#22312;&#20219;&#20309; <span class="t-lc"><a href="cpp-locale-locale.html">std::locale</a></span> &#23545;&#35937;&#23454;&#35013; <code>Facet</code> &#65292;&#21017;&#27492;&#20989;&#25968;&#25152;&#36820;&#22238;&#30340;&#24341;&#29992;&#23601;&#21512;&#27861;&#12290;</p>
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">&#24322;&#24120;</span></h3>
<p>&#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-locale-has_facet.html"><span class="kw1897">std::<span class="me2">has_facet</span></span></a><span class="sy1">&lt;</span>Facet<span class="sy1">&gt;</span><span class="br0">(</span>loc<span class="br0">)</span> <span class="sy1">==</span> <span class="kw2">false</span></span></span> &#21017;&#20026; <span class="t-lc"><a href="cpp-types-bad_cast.html">std::bad_cast</a></span> &#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
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<p>&#26174;&#31034;&#29992;&#25143;&#20559;&#22909;&#30340;&#26412;&#22320;&#29615;&#22659;&#25152;&#29992;&#30340; 3 &#23383;&#27597;&#37329;&#39069;&#21517;</p>
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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="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-locale-locale.html"><span class="kw1894">std::<span class="me2">locale</span></span></a> loc <span class="sy1">=</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;&quot;</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#29992;&#25143;&#20559;&#22909;&#30340;&#26412;&#22320;&#29615;&#22659;</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;Your currency string is &quot;</span>
<span class="sy1">&lt;&lt;</span> std<span class="sy4">::</span><span class="me2">use_facet</span><span class="sy1">&lt;</span><a href="cpp-locale-moneypunct.html"><span class="kw1971">std::<span class="me2">moneypunct</span></span></a><span class="sy1">&lt;</span><span class="kw4">char</span>, <span class="kw2">true</span><span class="sy1">&gt;&gt;</span><span class="br0">(</span>loc<span class="br0">)</span>.<span class="me1">curr_symbol</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>
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<p>&#36755;&#20986;&#65306;</p>
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<pre class="de1">Your currency string is USD</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-locale-locale.html"><span class="t-lines"><span>locale</span></span></a></div>
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<td>&#29992;&#20197;&#23553;&#35013;&#25991;&#21270;&#24046;&#24322;&#30340;&#22810;&#24577;&#21051;&#38754;&#30340;&#38598;&#21512;<br />
<span class="t-mark">(&#31867;)</span></td>
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<div><a href="cpp-locale-has_facet.html"><span class="t-lines"><span>has_facet</span></span></a></div>
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<td>&#26816;&#26597;&#26412;&#22320;&#29615;&#22659;&#26159;&#21542;&#23454;&#29616;&#29305;&#23450;&#30340;&#21051;&#38754;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
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