488 lines
31 KiB
HTML
488 lines
31 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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<title>std::codecvt</title>
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<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_locale_codecvt skin-cppreference2 action-view cpp-navbar">
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<div id="cpp-content-base">
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<div id="content"><a id="top"></a>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>codecvt</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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<table class="t-dcl-begin">
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<td>
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<div>定义于头文件 <code><a href="cpp-header-locale.html"><locale></a></code></div>
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<td></td>
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<td></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><br /></span>
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<p> <span class="kw1">class</span> InternT,<br />
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<span class="kw1">class</span> ExternT,<br />
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<span class="kw1">class</span> State<br /></p>
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<span class="sy1">></span> <span class="kw1">class</span> codecvt<span class="sy4">;</span></div>
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<td class="t-dcl-nopad"></td>
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<p>类模板 <code>std::codecvt</code> 封装字符串的转换，包括宽和多字节，从一种编码到另一种。通过 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-io-basic_fstream.html"><span class="kw1720">std::<span class="me2">basic_fstream</span></span></a><span class="sy1"><</span>CharT<span class="sy1">></span></span></span> 进行的所有 I/O 操作都使用流中感染的 <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">codecvt</span><span class="sy1"><</span>CharT, <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></span> 本地环境平面。</p>
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<div class="t-inheritance-diagram">
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<div class="center">
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<div class="noresize" style="height: 88px; width: 306px;"><map name="ImageMap_1_1093048360" id="ImageMap_1_1093048360">
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<area href="cpp-locale-codecvt_base.html" shape="rect" coords="5,4,107,36" alt="cpp/locale/codecvt base" />
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<area href="cpp-locale-locale-facet.html" shape="rect" coords="5,52,107,85" alt="cpp/locale/locale/facet" /></map><img alt="std-codecvt-inheritance.svg" src="std-codecvt-inheritance.svg" width="306" height="88" usemap="#ImageMap_1_1093048360" /></div>
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</div>
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<div style="text-align:center;">
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<p><span style="font-size:0.7em; line-height:130%">继承图</span></p>
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</div>
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</div>
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<p>标准库提供以下独立（本地环境无关）特化：</p>
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<table class="t-dsc-begin">
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<tr class="t-dsc-header">
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<td colspan="2">
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<div>定义于头文件 <code><a href="cpp-header-locale.html"><locale></a></code></div>
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</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">std<span class="sy4">::</span><span class="me2">codecvt</span><span class="sy1"><</span><span class="kw4">char</span>, <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></span></td>
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<td>恒等转换</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">std<span class="sy4">::</span><span class="me2">codecvt</span><span class="sy1"><</span><span class="kw4">char16_t</span>, <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></span></td>
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<td>在 UTF-16 和 UTF-8 间转换 <span class="t-mark-rev t-since-cxx11">(C++11 起)</span><span class="t-mark-rev t-deprecated-cxx20">(C++20 中弃用)</span></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">std<span class="sy4">::</span><span class="me2">codecvt</span><span class="sy1"><</span><span class="kw4">char16_t</span>, char8_t, <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></span></td>
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<td>在 UTF-16 和 UTF-8 间转换 <span class="t-mark-rev t-since-cxx20">(C++20 起)</span></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">std<span class="sy4">::</span><span class="me2">codecvt</span><span class="sy1"><</span><span class="kw4">char32_t</span>, <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></span></td>
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<td>在 UTF-32 和 UTF-8 间转换 <span class="t-mark-rev t-since-cxx11">(C++11 起)</span><span class="t-mark-rev t-deprecated-cxx20">(C++20 中弃用)</span></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">std<span class="sy4">::</span><span class="me2">codecvt</span><span class="sy1"><</span><span class="kw4">char32_t</span>, char8_t, <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></span></td>
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<td>在 UTF-32 和 UTF-8 间转换 <span class="t-mark-rev t-since-cxx20">(C++20 起)</span></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">std<span class="sy4">::</span><span class="me2">codecvt</span><span class="sy1"><</span><span class="kw4">wchar_t</span>, <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></span></td>
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<td>在系统原生宽和单字节窄字符集间转换</td>
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</tr>
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</table>
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<p>另外， C++ 程序中构造每个的 locale 对象实装上述特化其自身的（本地环境特定）版本。</p>
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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>
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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>
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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>State</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.E5.87.BD.E6.95.B0">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 t-dsc-member-nobold-div">
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<div><a href="cpp-locale-codecvt-codecvt.html"><span class="t-lines"><span>(构造函数)</span></span></a></div>
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</div>
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</td>
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<td>构造新的 codecvt 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><a href="cpp-locale-codecvt-~codecvt.html"><span class="t-lines"><span>(析构函数)</span></span></a></div>
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</div>
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</td>
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<td>销毁 codecvt 平面<br />
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<span class="t-mark">(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-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">(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">(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">(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">(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">(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">(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">(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=".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=".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">(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">(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">(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">(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">(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">(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">(虚受保护成员函数)</span></td>
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</tr>
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</table>
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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>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td><code>noconv</code></td>
|
|
<td>不要求转换，输入与输出类型相同</td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
|
|
<div class="t-example">
|
|
<p>下例示例用在 codecvt<wchar_t, char, mbstate_t> 实现 UTF-8 转换的本地环境读取 UTF-8 环境，并用 std::codecvt 的标准特化转换 UTF-8 字符串为 UTF-16</p>
|
|
<div class="t-example-live-link"></div>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="cpp source-cpp">
|
|
<pre class="de1"><span class="co2">#include <iostream></span>
|
|
<span class="co2">#include <fstream></span>
|
|
<span class="co2">#include <string></span>
|
|
<span class="co2">#include <locale></span>
|
|
<span class="co2">#include <iomanip></span>
|
|
<span class="co2">#include <codecvt></span>
|
|
|
|
<span class="co1">// 工具包装器，用于为 wstring/wbuffer 适配绑定到 locale 的平面</span>
|
|
<span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> Facet<span class="sy1">></span>
|
|
<span class="kw1">struct</span> deletable_facet <span class="sy4">:</span> Facet
|
|
<span class="br0">{</span>
|
|
<span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> ...<span class="me1">Args</span><span class="sy1">></span>
|
|
deletable_facet<span class="br0">(</span>Args<span class="sy3">&&</span> ...<span class="me1">args</span><span class="br0">)</span> <span class="sy4">:</span> Facet<span class="br0">(</span><a href="cpp-utility-forward.html"><span class="kw1117">std::<span class="me2">forward</span></span></a><span class="sy1"><</span>Args<span class="sy1">></span><span class="br0">(</span>args<span class="br0">)</span>...<span class="br0">)</span> <span class="br0">{</span><span class="br0">}</span>
|
|
~deletable_facet<span class="br0">(</span><span class="br0">)</span> <span class="br0">{</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>
|
|
<span class="co1">// UTF-8 窄多字节编码</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> data <span class="sy1">=</span> <span class="kw1">reinterpret_cast</span><span class="sy1"><</span><span class="kw4">const</span> <span class="kw4">char</span><span class="sy2">*</span><span class="sy1">></span><span class="br0">(</span><span class="sy2">+</span>u8<span class="st0">"z<span class="es3">\u00df</span><span class="es3">\u6c34</span><span class="es4">\U0001f34c</span>"</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<span class="co1">// 或 reinterpret_cast<const char*>(+u8"zß水🍌")</span>
|
|
<span class="co1">// 或 "\x7a\xc3\x9f\xe6\xb0\xb4\xf0\x9f\x8d\x8c"</span>
|
|
|
|
<a href="cpp-io-basic_ofstream.html"><span class="kw1733">std::<span class="me2">ofstream</span></span></a><span class="br0">(</span><span class="st0">"text.txt"</span><span class="br0">)</span> <span class="sy1"><<</span> data<span class="sy4">;</span>
|
|
|
|
<span class="co1">// 使用系统提供的本地环境的 codecvt 平面</span>
|
|
<a href="cpp-io-basic_ifstream.html"><span class="kw1746">std::<span class="me2">wifstream</span></span></a> fin<span class="br0">(</span><span class="st0">"text.txt"</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<span class="co1">// 从 wifstream 的读取将使用 codecvt<wchar_t, char, mbstate_t></span>
|
|
<span class="co1">// 此 locale 的 codecvt 从 UTF-8 转换到 UCS4 （在如 Linux 的系统上）</span>
|
|
fin.<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="st0">"en_US.UTF-8"</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"The UTF-8 file contains the following UCS4 code points: <span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">wchar_t</span> c<span class="sy4">;</span> fin <span class="sy1">>></span> c<span class="sy4">;</span> <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="st0">"U+"</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="sy1"><<</span> <a href="cpp-io-manip-setw.html"><span class="kw1797">std::<span class="me2">setw</span></span></a><span class="br0">(</span><span class="nu0">4</span><span class="br0">)</span> <span class="sy1"><<</span> <a href="cpp-io-manip-setfill.html"><span class="kw1795">std::<span class="me2">setfill</span></span></a><span class="br0">(</span><span class="st0">'0'</span><span class="br0">)</span> <span class="sy1"><<</span> c <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
|
|
|
|
<span class="co1">// 使用标准（本地环境无关） codecvt 平面</span>
|
|
<a href="cpp-locale-wstring_convert.html"><span class="kw1899">std::<span class="me2">wstring_convert</span></span></a><span class="sy1"><</span>
|
|
deletable_facet<span class="sy1"><</span>std<span class="sy4">::</span><span class="me2">codecvt</span><span class="sy1"><</span><span class="kw4">char16_t</span>, <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="kw4">char16_t</span><span class="sy1">></span> conv16<span class="sy4">;</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1234">std::<span class="me2">u16string</span></span></a> str16 <span class="sy1">=</span> conv16.<span class="me1">from_bytes</span><span class="br0">(</span>data<span class="br0">)</span><span class="sy4">;</span>
|
|
|
|
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"The UTF-8 file contains the following UTF-16 code points: <span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">char16_t</span> c <span class="sy4">:</span> str16<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="st0">"U+"</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="sy1"><<</span> <a href="cpp-io-manip-setw.html"><span class="kw1797">std::<span class="me2">setw</span></span></a><span class="br0">(</span><span class="nu0">4</span><span class="br0">)</span> <span class="sy1"><<</span> <a href="cpp-io-manip-setfill.html"><span class="kw1795">std::<span class="me2">setfill</span></span></a><span class="br0">(</span><span class="st0">'0'</span><span class="br0">)</span> <span class="sy1"><<</span> c <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
|
|
<span class="br0">}</span></pre></div>
|
|
</div>
|
|
<p>输出：</p>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="text source-text">
|
|
<pre class="de1">The UTF-8 file contains the following UCS4 code points:
|
|
U+007a
|
|
U+00df
|
|
U+6c34
|
|
U+1f34c
|
|
The UTF-8 file contains the following UTF-16 code points:
|
|
U+007a
|
|
U+00df
|
|
U+6c34
|
|
U+d83c
|
|
U+df4c</pre></div>
|
|
</div>
|
|
</div>
|
|
<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"><strong class="selflink"><tt>codecvt</tt></strong><char16_t, char, mbstate_t><br />
|
|
<a href="cpp-locale-codecvt_utf8_utf16.html"><tt>codecvt_utf8_utf16</tt></a><char16_t><br />
|
|
<a href="cpp-locale-codecvt_utf8_utf16.html"><tt>codecvt_utf8_utf16</tt></a><char32_t><br />
|
|
<a href="cpp-locale-codecvt_utf8_utf16.html"><tt>codecvt_utf8_utf16</tt></a><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><strong class="selflink"><tt>codecvt</tt></strong><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><<strong class="selflink"><tt>codecvt</tt></strong><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_base.html"><span class="t-lines"><span>codecvt_base</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>定义字符转换错误<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_byname.html"><span class="t-lines"><span>codecvt_byname</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>为具名本地环境构造 codecvt 平面<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_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>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-locale-codecvt_utf8_utf16.html"><span class="t-lines"><span>codecvt_utf8_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-8 与 UTF-16 间转换<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|