488 lines
29 KiB
HTML
488 lines
29 KiB
HTML
<!DOCTYPE html>
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<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
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<head><meta http-equiv="x-ua-compatible" content="ie=edge">
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
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<title>std::codecvt_utf8_utf16</title>
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<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_locale_codecvt_utf8_utf16 skin-cppreference2 action-view cpp-navbar">
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<div id="cpp-content-base">
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>codecvt_utf8_utf16</h1>
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<div id="bodyContent">
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-locale.html">locale</a></span></div>
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<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
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<td>
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<div>定义于头文件 <code><a href="cpp-header-codecvt.html"><codecvt></a></code></div>
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</td>
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<td></td>
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<td></td>
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<tr class="t-dcl t-since-cxx11">
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> Elem,<br /></span>
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<p> <span class="kw4">unsigned</span> <span class="kw4">long</span> Maxcode <span class="sy1">=</span> <span class="nu12">0x10ffff</span>,<br />
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<a href="cpp-locale-codecvt_mode.html"><span class="kw1985">std::<span class="me2">codecvt_mode</span></span></a> Mode <span class="sy1">=</span> <span class="br0">(</span><a href="cpp-locale-codecvt_mode.html"><span class="kw1985">std::<span class="me2">codecvt_mode</span></span></a><span class="br0">)</span><span class="nu0">0</span> <span class="sy1">></span><br /></p>
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<span class="kw1">class</span> codecvt_utf8_utf16 <span class="sy4">:</span> <span class="kw1">public</span> <a href="cpp-locale-codecvt.html"><span class="kw1939">std::<span class="me2">codecvt</span></span></a><span class="sy1"><</span>Elem, <span class="kw4">char</span>, <a href="cpp-string-multibyte-mbstate_t.html"><span class="kw1179">std::<span class="me2">mbstate_t</span></span></a><span class="sy1">></span><span class="sy4">;</span></div>
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<td class="t-dcl-nopad"></td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++17 中弃用)</span></td>
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<tr class="t-dcl-sep">
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<td></td>
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<p><span class="t-lc"><strong class="selflink">std::codecvt_utf8_utf16</strong></span> 是一个 <span class="t-lc"><a href="cpp-locale-codecvt.html">std::codecvt</a></span> 平面，封装 UTF-8 编码字节串和 UTF-16 编码字符串间的转换。若 <code>Elem</code> 为 32 位类型，则输出序列的每个 32 位字符中将存储一个 UTF-16 编码单元。</p>
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<p>这是 N:M 转换平面，而且不能为 <span class="t-lc"><a href="cpp-io-basic_filebuf.html">std::basic_filebuf</a></span> 所用（它只容许内部和外部编码间的 1:N 转换，例如 UTF-32/UTF-8 ）。此平面不能为 <span class="t-lc"><a href="cpp-locale-wstring_convert.html">std::wstring_convert</a></span> 所用。</p>
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<h3><span class="mw-headline" id=".E6.A8.A1.E6.9D.BF.E5.BD.A2.E5.8F.82">模板形参</span></h3>
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<table class="t-par-begin">
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<tr class="t-par">
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<td>Elem</td>
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<td>-</td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">char16_t</span></span></span> 、 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">char32_t</span></span></span> 或 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">wchar_t</span></span></span> 之一</td>
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</tr>
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<tr class="t-par">
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<td>Maxcode</td>
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<td>-</td>
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<td>此平面将读或写而不出错的 <code>Elem</code> 最大值</td>
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</tr>
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<tr class="t-par">
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<td>Mode</td>
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<td>-</td>
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<td><span class="t-lc"><a href="cpp-locale-codecvt_mode.html">std::codecvt_mode</a></span> 类型常量</td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.87.BD.E6.95.B0">成员函数</span></h3>
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<div class="t-dsc-member-div t-dsc-member-nobold-div">
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<div><strong class="selflink"><span class="t-lines"><span>(构造函数)</span></span></strong></div>
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</div>
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</td>
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<td>构造新的 <code>codecvt_utf8_utf16</code> 平面<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div t-dsc-member-nobold-div">
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<div><strong class="selflink"><span class="t-lines"><span>(析构函数)</span></span></strong></div>
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</div>
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</td>
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<td>销毁 <code>codecvt_utf8_utf16</code> 平面<br />
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<span class="t-mark">(公开成员函数)</span></td>
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</tr>
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</table>
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<div class="t-member">
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<h2><span class="mw-headline" id="std::codecvt_utf8_utf16::codecvt_utf8_utf16"><span style="font-size:0.7em; line-height:130%">std::codecvt_utf8_utf16::</span>codecvt_utf8_utf16</span></h2>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">explicit</span> codecvt_utf8_utf16<span class="br0">(</span> <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> refs <span class="sy1">=</span> <span class="nu0">0</span> <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td class="t-dcl-nopad"></td>
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<td class="t-dcl-nopad"></td>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</table>
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<p>构造新的 <code>std::codecvt_utf8_utf16</code> 平面，传递初始引用计数 <code>refs</code> 给基类。</p>
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<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
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<table class="t-par-begin">
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<tr class="t-par">
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<td>refs</td>
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<td>-</td>
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<td>链接到平面的引用数</td>
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</tr>
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</table>
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</div>
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<div class="t-member">
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<h2><span class="mw-headline" id="std::codecvt_utf8_utf16::.7Ecodecvt_utf8_utf16"><span style="font-size:0.7em; line-height:130%">std::codecvt_utf8_utf16::</span>~codecvt_utf8_utf16</span></h2>
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<table class="t-dcl-begin">
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<tr class="t-dcl">
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<td class="t-dcl-nopad">
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<div><span class="mw-geshi cpp source-cpp">~codecvt_utf8_utf16<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></span></div>
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<td class="t-dcl-nopad"></td>
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<td class="t-dcl-nopad"></td>
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</tr>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</tr>
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</tbody>
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</table>
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<p>销毁平面。不同于本地环境所管理的平面，此平面的析构函数为公开。</p>
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</div>
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<div class="t-inherited">
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<h2><span class="mw-headline" id=".E7.BB.A7.E6.89.BF.E8.87.AA_std::codecvt">继承自 <a href="cpp-locale-codecvt.html"><span style="font-size:0.7em; line-height:130%">std::</span>codecvt</a></span></h2>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E7.B1.BB.E5.9E.8B">成员类型</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc-hitem">
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<td>成员类型</td>
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<td>定义</td>
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<tr class="t-dsc">
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<td><code>intern_type</code></td>
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<td><code>internT</code></td>
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<tr class="t-dsc">
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<td><code>extern_type</code></td>
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<td><code>externT</code></td>
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</tr>
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<tr class="t-dsc">
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<td><code>state_type</code></td>
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<td><code>stateT</code></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.AF.B9.E8.B1.A1">成员对象</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc-hitem">
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<td>成员名</td>
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<td>类型</td>
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</tr>
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<tr class="t-dsc">
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<td><code>id</code> <span class="t-cmark">[静态]</span></td>
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<td><span class="t-lc"><a href="cpp-locale-locale-id.html">std::locale::id</a></span></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.87.BD.E6.95.B0_2">成员函数</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-out.html"><span class="t-lines"><span>out</span></span></a></div>
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</div>
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</td>
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<td>调用 <code>do_out</code><br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-in.html"><span class="t-lines"><span>in</span></span></a></div>
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</div>
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</td>
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<td>调用 <code>do_in</code><br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-unshift.html"><span class="t-lines"><span>unshift</span></span></a></div>
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</div>
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</td>
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<td>调用 <code>do_unshift</code><br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-encoding.html"><span class="t-lines"><span>encoding</span></span></a></div>
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</div>
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</td>
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<td>调用 <code>do_encoding</code><br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-always_noconv.html"><span class="t-lines"><span>always_noconv</span></span></a></div>
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</div>
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</td>
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<td>调用 <code>do_always_noconv</code><br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-length.html"><span class="t-lines"><span>length</span></span></a></div>
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</div>
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</td>
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<td>调用 <code>do_length</code><br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的公开成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-max_length.html"><span class="t-lines"><span>max_length</span></span></a></div>
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</div>
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</td>
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<td>调用 <code>do_max_length</code><br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的公开成员函数)</span></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E5.8F.97.E4.BF.9D.E6.8A.A4.E6.88.90.E5.91.98.E5.87.BD.E6.95.B0">受保护成员函数</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-out.html"><span class="t-lines"><span>do_out</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-cmark">[虚]</span></span></span></div>
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</div>
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</td>
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<td>从 internT 转换字符串为 externT 转换字符串，如在写入文件时<br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的虚受保护成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-in.html"><span class="t-lines"><span>do_in</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-cmark">[虚]</span></span></span></div>
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</div>
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</td>
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<td>从 externT 转换字符串为 internT ，如在从文件读取时<br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的虚受保护成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-unshift.html"><span class="t-lines"><span>do_unshift</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-cmark">[虚]</span></span></span></div>
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</div>
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</td>
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<td>为不完整转换生成 externT 字符的终止字符序列<br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的虚受保护成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-encoding.html"><span class="t-lines"><span>do_encoding</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-cmark">[虚]</span></span></span></div>
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</div>
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</td>
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<td>返回产生一个 internT 字符所需的 externT 字符数，若此值为常数<br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的虚受保护成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-always_noconv.html"><span class="t-lines"><span>do_always_noconv</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-cmark">[虚]</span></span></span></div>
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</div>
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</td>
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<td>测试平面编码是否对所有合法值为恒等转换<br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的虚受保护成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-length.html"><span class="t-lines"><span>do_length</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-cmark">[虚]</span></span></span></div>
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</div>
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</td>
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<td>计算转换成给定的 internT 缓冲区会消耗的 externT 字符串长度<br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的虚受保护成员函数)</span></td>
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</tr>
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-locale-codecvt-max_length.html"><span class="t-lines"><span>do_max_length</span></span></a></div>
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<div><span class="t-lines"><span><span class="t-cmark">[虚]</span></span></span></div>
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</div>
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</td>
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<td>返回能转换成单个 internT 字符的最大 externT 字符数<br />
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<span class="t-mark">(<code>std::codecvt<InternT,ExternT,State></code> 的虚受保护成员函数)</span></td>
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</tr>
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</table>
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<p><br /></p>
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</div>
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<div class="t-inherited">
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<h2><span class="mw-headline" id=".E7.BB.A7.E6.89.BF.E8.87.AA_std::codecvt_base">继承自 <a href="cpp-locale-codecvt_base.html"><span style="font-size:0.7em; line-height:130%">std::</span>codecvt_base</a></span></h2>
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<table class="t-dsc-begin">
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<tr class="t-dsc-hitem">
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<td>成员类型</td>
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<td>定义</td>
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</tr>
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<tr class="t-dsc">
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">enum</span> result <span class="br0">{</span> ok, partial, error, noconv <span class="br0">}</span><span class="sy4">;</span></span></span></td>
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<td>无作用域枚举类型</td>
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</tr>
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</table>
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<table class="t-dsc-begin">
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<tr class="t-dsc-hitem">
|
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<td>枚举常量</td>
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<td>定义</td>
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</tr>
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<tr class="t-dsc">
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<td><code>ok</code></td>
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<td>完成转换而无错误</td>
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</tr>
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<tr class="t-dsc">
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<td><code>partial</code></td>
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<td>未转换所有源字符</td>
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</tr>
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<tr class="t-dsc">
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<td><code>error</code></td>
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<td>遇到非法字符</td>
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</tr>
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<tr class="t-dsc">
|
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<td><code>noconv</code></td>
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<td>不要求转换，输入与输出类型相同</td>
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</tr>
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</table>
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</div>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
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<div class="t-example">
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<div class="t-example-live-link"></div>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="cpp source-cpp">
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<pre class="de1"><span class="co2">#include <iostream></span>
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<span class="co2">#include <string></span>
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<span class="co2">#include <codecvt></span>
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<span class="co2">#include <cassert></span>
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<span class="co2">#include <locale></span>
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<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
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<span class="br0">{</span>
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<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> u8 <span class="sy1">=</span> u8<span class="st0">"z<span class="es3">\u00df</span><span class="es3">\u6c34</span><span class="es4">\U0001f34c</span>"</span><span class="sy4">;</span>
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<a href="cpp-string-basic_string.html"><span class="kw1234">std::<span class="me2">u16string</span></span></a> u16 <span class="sy1">=</span> u<span class="st0">"z<span class="es3">\u00df</span><span class="es3">\u6c34</span><span class="es4">\U0001f34c</span>"</span><span class="sy4">;</span>
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<span class="co1">// UTF-8 到 UTF-16/char16_t</span>
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<a href="cpp-string-basic_string.html"><span class="kw1234">std::<span class="me2">u16string</span></span></a> u16_conv <span class="sy1">=</span> <a href="cpp-locale-wstring_convert.html"><span class="kw1899">std::<span class="me2">wstring_convert</span></span></a><span class="sy1"><</span>
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std<span class="sy4">::</span><span class="me2">codecvt_utf8_utf16</span><span class="sy1"><</span><span class="kw4">char16_t</span><span class="sy1">></span>, <span class="kw4">char16_t</span><span class="sy1">></span><span class="br0">{</span><span class="br0">}</span>.<span class="me1">from_bytes</span><span class="br0">(</span>u8<span class="br0">)</span><span class="sy4">;</span>
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<a href="cpp-error-assert.html"><span class="kw774">assert</span></a><span class="br0">(</span>u16 <span class="sy1">==</span> u16_conv<span class="br0">)</span><span class="sy4">;</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"UTF-8 to UTF-16 conversion produced "</span>
|
|
<span class="sy1"><<</span> u16_conv.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">" code units:<span class="es1">\n</span>"</span><span class="sy4">;</span>
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<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">char16_t</span> c <span class="sy4">:</span> u16_conv<span class="br0">)</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-hex.html"><span class="kw1782">std::<span class="me2">hex</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-showbase.html"><span class="kw1766">std::<span class="me2">showbase</span></span></a> <span class="sy1"><<</span> c <span class="sy1"><<</span> <span class="st0">' '</span><span class="sy4">;</span>
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|
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<span class="co1">// UTF-16/char16_t 到 UTF-8</span>
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<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> u8_conv <span class="sy1">=</span> <a href="cpp-locale-wstring_convert.html"><span class="kw1899">std::<span class="me2">wstring_convert</span></span></a><span class="sy1"><</span>
|
|
std<span class="sy4">::</span><span class="me2">codecvt_utf8_utf16</span><span class="sy1"><</span><span class="kw4">char16_t</span><span class="sy1">></span>, <span class="kw4">char16_t</span><span class="sy1">></span><span class="br0">{</span><span class="br0">}</span>.<span class="me1">to_bytes</span><span class="br0">(</span>u16<span class="br0">)</span><span class="sy4">;</span>
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<a href="cpp-error-assert.html"><span class="kw774">assert</span></a><span class="br0">(</span>u8 <span class="sy1">==</span> u8_conv<span class="br0">)</span><span class="sy4">;</span>
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|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"<span class="es1">\n</span>UTF-16 to UTF-8 conversion produced "</span>
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|
<span class="sy1"><<</span> <a href="cpp-io-manip-hex.html"><span class="kw1781">std::<span class="me2">dec</span></span></a> <span class="sy1"><<</span> u8_conv.<span class="me1">size</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">" bytes:<span class="es1">\n</span>"</span> <span class="sy1"><<</span> <a href="cpp-io-manip-hex.html"><span class="kw1782">std::<span class="me2">hex</span></span></a><span class="sy4">;</span>
|
|
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">char</span> c <span class="sy4">:</span> u8_conv<span class="br0">)</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="sy2">+</span><span class="br0">(</span><span class="kw4">unsigned</span> <span class="kw4">char</span><span class="br0">)</span>c <span class="sy1"><<</span> <span class="st0">' '</span><span class="sy4">;</span>
|
|
<span class="br0">}</span></pre></div>
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</div>
|
|
<p>输出：</p>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="text source-text">
|
|
<pre class="de1">UTF-8 to UTF-16 conversion produced 5 code units:
|
|
0x7a 0xdf 0x6c34 0xd83c 0xdf4c
|
|
UTF-16 to UTF-8 conversion produced 10 bytes:
|
|
0x7a 0xc3 0x9f 0xe6 0xb0 0xb4 0xf0 0x9f 0x8d 0x8c</pre></div>
|
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</div>
|
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</div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
|
|
<table class="wikitable" style="font-size:85%; text-align:center;">
|
|
<tr>
|
|
<th>字符转换</th>
|
|
<th>本地环境定义多字节<br />
|
|
(UTF-8, GB18030)</th>
|
|
<th>UTF-8<br /></th>
|
|
<th>UTF-16<br /></th>
|
|
</tr>
|
|
<tr>
|
|
<th>UTF-16</th>
|
|
<td style="background: #90ff90; color: black; vertical-align: middle; text-align: center;" class="table-yes"><a href="cpp-string-multibyte-mbrtoc16.html"><tt>mbrtoc16</tt></a> / <a href="cpp-string-multibyte-c16rtomb.html"><tt>c16rtomb</tt></a><span class="t-mark">(有 C11 的 DR488)</span></td>
|
|
<td style="background: #90ff90; color: black; vertical-align: middle; text-align: center;" class="table-yes"><a href="cpp-locale-codecvt.html"><tt>codecvt</tt></a><char16_t, char, mbstate_t><br />
|
|
<strong class="selflink"><tt>codecvt_utf8_utf16</tt></strong><char16_t><br />
|
|
<strong class="selflink"><tt>codecvt_utf8_utf16</tt></strong><char32_t><br />
|
|
<strong class="selflink"><tt>codecvt_utf8_utf16</tt></strong><wchar_t></td>
|
|
<td style="background: #ececec; color: grey; vertical-align: middle; text-align: center;" class="table-na"><small>N/A</small></td>
|
|
</tr>
|
|
<tr>
|
|
<th>UCS2</th>
|
|
<td style="background: #90ff90; color: black; vertical-align: middle; text-align: center;" class="table-yes"><a href="cpp-string-multibyte-c16rtomb.html"><tt>c16rtomb</tt></a><span class="t-mark">(无 C11 的 DR488)</span></td>
|
|
<td style="background: #90ff90; color: black; vertical-align: middle; text-align: center;" class="table-yes"><a href="cpp-locale-codecvt_utf8.html"><tt>codecvt_utf8</tt></a><char16_t><br />
|
|
<p><a href="cpp-locale-codecvt_utf8.html"><tt>codecvt_utf8</tt></a><wchar_t><span class="t-mark">(Windows)</span></p>
|
|
</td>
|
|
<td style="background: #90ff90; color: black; vertical-align: middle; text-align: center;" class="table-yes"><a href="cpp-locale-codecvt_utf16.html"><tt>codecvt_utf16</tt></a><char16_t><br />
|
|
<p><a href="cpp-locale-codecvt_utf16.html"><tt>codecvt_utf16</tt></a><wchar_t><span class="t-mark">(Windows)</span></p>
|
|
</td>
|
|
</tr>
|
|
<tr>
|
|
<th>UTF-32</th>
|
|
<td style="background: #90ff90; color: black; vertical-align: middle; text-align: center;" class="table-yes">
|
|
<p><a href="cpp-string-multibyte-mbrtoc32.html"><tt>mbrtoc32</tt></a> / <a href="cpp-string-multibyte-c32rtomb.html"><tt>c32rtomb</tt></a></p>
|
|
</td>
|
|
<td style="background: #90ff90; color: black; vertical-align: middle; text-align: center;" class="table-yes">
|
|
<p><a href="cpp-locale-codecvt.html"><tt>codecvt</tt></a><char32_t, char, mbstate_t><br />
|
|
<a href="cpp-locale-codecvt_utf8.html"><tt>codecvt_utf8</tt></a><char32_t><br />
|
|
<a href="cpp-locale-codecvt_utf8.html"><tt>codecvt_utf8</tt></a><wchar_t><span class="t-mark">(非 Windows)</span></p>
|
|
</td>
|
|
<td style="background: #90ff90; color: black; vertical-align: middle; text-align: center;" class="table-yes">
|
|
<p><a href="cpp-locale-codecvt_utf16.html"><tt>codecvt_utf16</tt></a><char32_t><br />
|
|
<a href="cpp-locale-codecvt_utf16.html"><tt>codecvt_utf16</tt></a><wchar_t><span class="t-mark">(非 Windows)</span></p>
|
|
</td>
|
|
</tr>
|
|
<tr>
|
|
<th>系统宽<br />
|
|
UTF-32<span class="t-mark">(非 Windows)</span><br />
|
|
UCS2<span class="t-mark">(Windows)</span></th>
|
|
<td style="background: #90ff90; color: black; vertical-align: middle; text-align: center;" class="table-yes">
|
|
<p><a href="cpp-string-multibyte-mbsrtowcs.html"><tt>mbsrtowcs</tt></a> / <a href="cpp-string-multibyte-wcsrtombs.html"><tt>wcsrtombs</tt></a><br />
|
|
<a href="cpp-locale-use_facet.html"><tt>use_facet</tt></a><<a href="cpp-locale-codecvt.html"><tt>codecvt</tt></a><br />
|
|
<wchar_t, char, mbstate_t>>(<a href="cpp-locale-locale.html"><tt>locale</tt></a>)</p>
|
|
</td>
|
|
<td style="background:#ff9090; color:black; vertical-align: middle; text-align: center;" class="table-no">无</td>
|
|
<td style="background:#ff9090; color:black; vertical-align: middle; text-align: center;" class="table-no">无</td>
|
|
</tr>
|
|
</table>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-locale-codecvt.html"><span class="t-lines"><span>codecvt</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>在字符编码间转换，包括 UTF-8、UTF-16、UTF-32<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-locale-codecvt_mode.html"><span class="t-lines"><span>codecvt_mode</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span><span class="t-mark-rev t-deprecated-cxx17">(C++17 中弃用)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>用于改变标准 codecvt 刻面行为的标签<br />
|
|
<span class="t-mark">(枚举)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-locale-codecvt_utf8.html"><span class="t-lines"><span>codecvt_utf8</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span><span class="t-mark-rev t-deprecated-cxx17">(C++17 中弃用)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>在 UTF-8 与 UCS2/UCS4 间转换<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-locale-codecvt_utf16.html"><span class="t-lines"><span>codecvt_utf16</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span><span class="t-mark-rev t-deprecated-cxx17">(C++17 中弃用)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>在 UTF-16 与 UCS2/UCS4 间转换<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
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</div>
|
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</body>
|
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</html>
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