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

376 lines
43 KiB
HTML
Raw Permalink Blame History

<!DOCTYPE html>
<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
<head><meta http-equiv="x-ua-compatible" content="ie=edge">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>std::shared_ptr&lt;T&gt;::shared_ptr</title>
<link rel="stylesheet" href="ext.css" />
<link rel="stylesheet" href="site_modules.css" />
</head>
<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_memory_shared_ptr_shared_ptr skin-cppreference2 action-view cpp-navbar">
<div id="cpp-content-base">
<div id="content"><a id="top"></a>
<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::shared_ptr&lt;T&gt;::</span>shared_ptr</h1>
<div id="bodyContent">
<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-memory.html">memory</a>&lrm; | <a href="cpp-memory-shared_ptr.html">shared ptr</a></span></div>
<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
<table class="t-dcl-begin">
<tbody>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> shared_ptr<span class="br0">(</span><span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
</td>
<td>(1)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> shared_ptr<span class="br0">(</span> <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a> <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
</td>
<td>(2)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y <span class="sy1">&gt;</span><br />
<span class="kw1">explicit</span> shared_ptr<span class="br0">(</span> Y<span class="sy2">*</span> ptr <span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td>(3)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y, <span class="kw1">class</span> Deleter <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> Y<span class="sy2">*</span> ptr, Deleter d <span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td>(4)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Deleter <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a> ptr, Deleter d <span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td>(5)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y, <span class="kw1">class</span> Deleter, <span class="kw1">class</span> Alloc <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> Y<span class="sy2">*</span> ptr, Deleter d, Alloc alloc <span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td>(6)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Deleter, <span class="kw1">class</span> Alloc <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> <a href="cpp-types-nullptr_t.html"><span class="kw102">std::<span class="me2">nullptr_t</span></span></a> ptr, Deleter d, Alloc alloc <span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td>(7)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> <span class="kw4">const</span> shared_ptr<span class="sy1">&lt;</span>Y<span class="sy1">&gt;</span><span class="sy3">&amp;</span> r, element_type<span class="sy2">*</span> ptr <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
</td>
<td>(8)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl t-since-cxx20">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> shared_ptr<span class="sy1">&lt;</span>Y<span class="sy1">&gt;</span><span class="sy3">&amp;&amp;</span> r, element_type<span class="sy2">*</span> ptr <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
</td>
<td>(8)</td>
<td><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp">shared_ptr<span class="br0">(</span> <span class="kw4">const</span> shared_ptr<span class="sy3">&amp;</span> r <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
</td>
<td>(9)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> <span class="kw4">const</span> shared_ptr<span class="sy1">&lt;</span>Y<span class="sy1">&gt;</span><span class="sy3">&amp;</span> r <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
</td>
<td>(9)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp">shared_ptr<span class="br0">(</span> shared_ptr<span class="sy3">&amp;&amp;</span> r <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
</td>
<td>(10)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> shared_ptr<span class="sy1">&lt;</span>Y<span class="sy1">&gt;</span><span class="sy3">&amp;&amp;</span> r <span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
</td>
<td>(10)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y <span class="sy1">&gt;</span><br />
<span class="kw1">explicit</span> shared_ptr<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-memory-weak_ptr.html"><span class="kw741">std::<span class="me2">weak_ptr</span></span></a><span class="sy1">&lt;</span>Y<span class="sy1">&gt;</span><span class="sy3">&amp;</span> r <span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td>(11)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl t-until-cxx17">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> <a href="cpp-memory-auto_ptr.html"><span class="kw742">std::<span class="me2">auto_ptr</span></span></a><span class="sy1">&lt;</span>Y<span class="sy1">&gt;</span><span class="sy3">&amp;&amp;</span> r <span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td>(12)</td>
<td><span class="t-mark-rev t-until-cxx17">(C++17 &#20013;&#31227;&#38500;)</span></td>
</tr>
<tr class="t-dcl">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Y, <span class="kw1">class</span> Deleter <span class="sy1">&gt;</span><br />
shared_ptr<span class="br0">(</span> <a href="cpp-memory-unique_ptr.html"><span class="kw733">std::<span class="me2">unique_ptr</span></span></a><span class="sy1">&lt;</span>Y,Deleter<span class="sy1">&gt;</span><span class="sy3">&amp;&amp;</span> r <span class="br0">)</span><span class="sy4">;</span></span></div>
</td>
<td>(13)</td>
<td class="t-dcl-nopad"></td>
</tr>
<tr class="t-dcl-sep">
<td></td>
<td></td>
<td></td>
</tr>
</tbody>
</table>
<p>&#20174;&#25351;&#20195;&#35201;&#31649;&#29702;&#30340;&#23545;&#35937;&#30340;&#21508;&#31181;&#25351;&#38024;&#31867;&#22411;&#26500;&#36896;&#26032;&#30340; <code>shared_ptr</code> &#12290;</p>
<table class="t-rev-begin">
<tr class="t-rev t-since-cxx17">
<td>
<p>&#20026;&#20197;&#19979;&#25551;&#36848;&#30340;&#30446;&#30340;&#65292;&#33509;&#25351;&#38024;&#31867;&#22411; <code>Y*</code> &#21487;&#36716;&#25442;&#20026;&#25351;&#38024;&#31867;&#22411; <code>T*</code> &#65292;&#25110; <code>Y</code> &#26159; <code>U[N]</code> &#31867;&#22411;&#25968;&#32452;&#32780; <code>T</code> &#26159; <code>U cv []</code> &#65288;&#20854;&#20013; cv &#26159;&#26576;&#20010; cv &#38480;&#23450;&#31526;&#38598;&#21512;&#65289;&#65292;&#21017;&#35828; <code>Y*</code> <i>&#20860;&#23481;</i> <code>T*</code> &#12290;</p>
</td>
<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
</tr>
</table>
<div class="t-li1"><span class="t-li">1-2)</span> &#26500;&#36896;&#26080;&#34987;&#31649;&#29702;&#23545;&#35937;&#30340; <code>shared_ptr</code> &#65292;&#21363;&#31354; <code>shared_ptr</code> &#12290;</div>
<div class="t-li1"><span class="t-li">3-7)</span> &#26500;&#36896; <code>shared_ptr</code> &#65292;&#31649;&#29702; <code>ptr</code> &#25152;&#25351;&#21521;&#30340;&#23545;&#35937;&#12290;
<table class="t-rev-begin">
<tr class="t-rev t-until-cxx17">
<td>
<p>&#23545;&#20110; <span class="t-v">(3-4,6)</span> &#65292; <code>Y*</code> &#24517;&#39035;&#21487;&#36716;&#25442;&#20026; <code>T*</code> &#12290;</p>
</td>
<td><span class="t-mark-rev t-until-cxx17">(C++17 &#21069;)</span></td>
</tr>
<tr class="t-rev t-since-cxx17">
<td>
<p>&#33509; <code>T</code> &#26159;&#25968;&#32452;&#31867;&#22411; <code>U[N]</code> &#65292;&#21017;&#33509; <code>Y(*)[N]</code> &#19981;&#21487;&#36716;&#25442;&#20026; <code>T*</code> &#21017; <span class="t-v">(3-4,6)</span> &#19981;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;&#33509; <code>T</code> &#26159;&#25968;&#32452;&#31867;&#22411; <code>U[]</code> &#65292;&#21017;&#33509; <code>Y(*)[]</code> &#19981;&#21487;&#36716;&#25442;&#20026; <code>T*</code> &#21017; <span class="t-v">(3-4,6)</span> &#19981;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;&#21542;&#21017;&#65292;&#33509; <code>Y*</code> &#19981;&#21487;&#36716;&#25442;&#20026; <code>T*</code> &#21017; <span class="t-v">(3-4,6)</span> &#19981;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;</p>
</td>
<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
</tr>
</table>
&#21478;&#22806;&#65306;</div>
<div class="t-li2"><span class="t-li">3)</span> &#20197; <a href="cpp-language-delete.html">delete &#34920;&#36798;&#24335;</a> <span class="t-c"><span class="mw-geshi cpp source-cpp">delete ptr</span></span> &#20026;&#21024;&#38500;&#22120;<span class="t-rev-inl t-since-cxx17"><span>&#65292;&#33509; <code>T</code> &#19981;&#26159;&#25968;&#32452;&#31867;&#22411;&#65307;&#20197; <span class="t-c"><span class="mw-geshi cpp source-cpp">delete<span class="br0">[</span><span class="br0">]</span> ptr</span></span> &#20026;&#21024;&#38500;&#22120;&#65292;&#33509; <code>T</code> &#26159;&#25968;&#32452;&#31867;&#22411;</span> <span><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></span></span>&#12290; <code>Y</code> &#24517;&#39035;&#26159;&#23436;&#25972;&#31867;&#22411;&#12290; delete &#34920;&#36798;&#24335;&#24517;&#39035;&#20026;&#33391;&#26500;&#65292;&#25317;&#26377;&#33391;&#22909;&#23450;&#20041;&#34892;&#20026;&#19988;&#19981;&#25243;&#24322;&#24120;&#12290;<span class="t-rev-inl t-since-cxx17"><span>&#33509; delete &#34920;&#36798;&#24335;&#19981;&#20026;&#33391;&#26500;&#65292;&#21017;&#27492;&#26500;&#36896;&#20989;&#25968;&#19981;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;</span> <span><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></span></span></div>
<div class="t-li2"><span class="t-li">4-5)</span> &#20197;&#25351;&#23450;&#30340;&#21024;&#38500;&#22120; <code>d</code> &#20026;&#21024;&#38500;&#22120;&#12290;&#34920;&#36798;&#24335; <span class="t-c"><span class="mw-geshi cpp source-cpp">d<span class="br0">(</span>ptr<span class="br0">)</span></span></span> &#34920;&#36798;&#24335;&#24517;&#39035;&#20026;&#33391;&#26500;&#65292;&#25317;&#26377;&#33391;&#22909;&#23450;&#20041;&#34892;&#20026;&#19988;&#19981;&#25243;&#24322;&#24120;&#12290; <code>d</code> &#30340;&#26500;&#36896;&#21644;&#20174; <code>d</code> &#26500;&#36896;&#23384;&#20648;&#30340;&#21024;&#38500;&#22120;&#24517;&#39035;&#19981;&#25243;&#24322;&#24120;&#12290;
<table class="t-rev-begin">
<tr class="t-rev t-until-cxx17">
<td>
<p><code>Deleter</code> &#24517;&#39035;<a href="cpp-named_req-CopyConstructible.html"><span style="font-style:italic">&#21487;&#22797;&#21046;&#26500;&#36896;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(CopyConstructible)</span></a> &#12290;</p>
</td>
<td><span class="t-mark-rev t-until-cxx17">(C++17 &#21069;)</span></td>
</tr>
<tr class="t-rev t-since-cxx17">
<td>
<p>&#33509;&#34920;&#36798;&#24335; <span class="t-c"><span class="mw-geshi cpp source-cpp">d<span class="br0">(</span>ptr<span class="br0">)</span></span></span> &#38750;&#33391;&#26500;&#65292;&#25110;&#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-types-is_move_constructible.html"><span class="kw538">std::<span class="me2">is_move_constructible</span></span></a><span class="sy1">&lt;</span>D<span class="sy1">&gt;</span><span class="sy4">::</span><span class="me2">value</span></span></span> &#20026; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> &#65292;&#21017;&#36825;&#20123;&#26500;&#36896;&#20989;&#25968;&#19981;&#39069;&#22806;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;</p>
</td>
<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
</tr>
</table>
</div>
<div class="t-li2"><span class="t-li">6-7)</span> &#21516; <span class="t-v">(4-5)</span> &#65292;&#20294;&#39069;&#22806;&#22320;&#29992; <code>alloc</code> &#30340;&#21103;&#26412;&#20998;&#37197;&#20869;&#37096;&#20351;&#29992;&#30340;&#25968;&#25454;&#12290; <code>Alloc</code> &#24517;&#39035;&#26159;<a href="cpp-named_req-Allocator.html"><span style="font-style:italic">&#20998;&#37197;&#22120;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(Allocator)</span></a> &#12290;</div>
<div class="t-li1"><span class="t-li">8)</span> <i>&#21035;&#21517;&#20351;&#29992;&#26500;&#36896;&#20989;&#25968;</i>&#65306;&#26500;&#36896; <code>shared_ptr</code> &#65292;&#19982; <code>r</code> &#30340;&#21021;&#22987;&#20540;&#20849;&#20139;&#25152;&#26377;&#26435;&#20449;&#24687;&#65292;&#20294;&#20445;&#26377;&#26080;&#20851;&#19988;&#19981;&#31649;&#29702;&#30340;&#25351;&#38024; <code>ptr</code> &#12290;&#33509;&#27492; <code>shared_ptr</code> &#26159;&#31163;&#24320;&#20316;&#29992;&#22495;&#30340;&#32452;&#20013;&#30340;&#26368;&#21518;&#32773;&#65292;&#21017;&#23427;&#23558;&#35843;&#29992;&#26368;&#21021; <code>r</code> &#25152;&#31649;&#29702;&#23545;&#35937;&#30340;&#26512;&#26500;&#20989;&#25968;&#12290;&#28982;&#32780;&#65292;&#22312;&#27492; <code>shared_ptr</code> &#19978;&#35843;&#29992; <code>get()</code> &#23558;&#22987;&#32456;&#36820;&#22238; <code>ptr</code> &#30340;&#21103;&#26412;&#12290;&#31243;&#24207;&#21592;&#36127;&#36131;&#30830;&#20445;&#21482;&#35201;&#27492; <code>shared_ptr</code> &#23384;&#22312;&#65292;&#27492; <code>ptr</code> &#23601;&#20445;&#25345;&#21512;&#27861;&#65292;&#20363;&#22914;&#22312;&#20856;&#22411;&#20351;&#29992;&#24773;&#20917;&#20013;&#65292;&#20854;&#20013; <code>ptr</code> &#26159; <code>r</code> &#25152;&#31649;&#29702;&#23545;&#35937;&#30340;&#25104;&#21592;&#65292;&#25110;&#26159; <code>r.get()</code> &#30340;&#21035;&#21517;&#65288;&#20363;&#22914;&#21521;&#19979;&#36716;&#22411;&#65289;&#12290;<span class="t-rev-inl t-since-cxx20"><span>&#23545;&#20110;&#25509;&#25910;&#21491;&#20540;&#30340;&#31532;&#20108;&#37325;&#36733;&#65292;&#35843;&#29992;&#21518; <code>r</code> &#20026;&#31354;&#19988; <span class="t-c"><span class="mw-geshi cpp source-cpp">r.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> nullptr</span></span> &#12290;</span> <span><span class="t-mark-rev t-since-cxx20">(C++20 &#36215;)</span></span></span></div>
<div class="t-li1"><span class="t-li">9)</span> &#26500;&#36896; <code>shared_ptr</code> &#65292;&#20849;&#20139; <code>r</code> &#25152;&#31649;&#29702;&#23545;&#35937;&#30340;&#25152;&#26377;&#26435;&#12290;&#33509; <code>r</code> &#19981;&#31649;&#29702;&#23545;&#35937;&#65292;&#21017; <code>*this</code> &#20134;&#19981;&#31649;&#29702;&#23545;&#35937;&#12290;&#33509; <code>Y*</code> &#19981;<span class="t-rev-inl t-until-cxx17"><span>&#21487;&#38544;&#24335;&#36716;&#25442;&#20026;</span> <span><span class="t-mark-rev t-until-cxx17">(C++17 &#21069;)</span></span></span><span class="t-rev-inl t-since-cxx17"><span><i>&#20860;&#23481;</i></span> <span><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></span></span> <code>T*</code> &#65292;&#21017;&#27169;&#26495;&#37325;&#36733;&#19981;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;</div>
<div class="t-li1"><span class="t-li">10)</span> &#20174; <code>r</code> &#31227;&#21160;&#26500;&#36896; <code>shared_ptr</code> &#12290;&#26500;&#36896;&#21518;&#65292; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> &#21547; <code>r</code> &#20808;&#21069;&#29366;&#24577;&#30340;&#21103;&#26412;&#65292;&#32780; <code>r</code> &#20026;&#31354;&#19988;&#20854;&#23384;&#20648;&#30340;&#25351;&#38024;&#20026;&#31354;&#12290;&#33509; <code>Y*</code> &#19981;<span class="t-rev-inl t-until-cxx17"><span>&#21487;&#38544;&#24335;&#36716;&#25442;&#20026;</span> <span><span class="t-mark-rev t-until-cxx17">(C++17 &#21069;)</span></span></span><span class="t-rev-inl t-since-cxx17"><span><i>&#20860;&#23481;</i></span> <span><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></span></span> <code>T*</code> &#65292;&#21017;&#27169;&#26495;&#37325;&#36733;&#19981;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;</div>
<div class="t-li1"><span class="t-li">11)</span> &#26500;&#36896; <code>shared_ptr</code> &#65292;&#20849;&#20139; <code>r</code> &#25152;&#31649;&#29702;&#23545;&#35937;&#30340;&#25152;&#26377;&#26435;&#12290; <span class="t-rev-inl t-until-cxx17"><span><code>Y*</code> &#24517;&#39035;&#21487;&#38544;&#24335;&#36716;&#25442;&#20026; <code>T*</code> &#12290;</span> <span><span class="t-mark-rev t-until-cxx17">(C++17 &#21069;)</span></span></span><span class="t-rev-inl t-since-cxx17"><span>&#27492;&#37325;&#36733;&#20165;&#33509; <code>Y*</code> &#20860;&#23481; <code>T*</code> &#25165;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;</span> <span><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></span></span>&#27880;&#24847;&#21487;&#20026;&#30456;&#21516;&#30446;&#30340;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">r.<span class="me1">lock</span><span class="br0">(</span><span class="br0">)</span></span></span> &#65306;&#21306;&#21035;&#26159;&#33509;&#21442;&#25968;&#20026;&#31354;&#21017;&#27492;&#26500;&#36896;&#20989;&#25968;&#25243;&#24322;&#24120;&#65292;&#32780; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-memory-weak_ptr.html"><span class="kw741">std::<span class="me2">weak_ptr</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span><span class="sy4">::</span><span class="me2">lock</span><span class="br0">(</span><span class="br0">)</span></span></span> &#22312;&#35813;&#24773;&#20917;&#19979;&#26500;&#36896;&#31354;&#30340; <code>std::shared_ptr</code> &#12290;</div>
<div class="t-li1"><span class="t-li">12)</span> &#26500;&#36896; <code>shared_ptr</code> &#65292;&#23384;&#20648;&#24182;&#21344;&#26377; <code>r</code> &#20808;&#21069;&#21344;&#26377;&#30340;&#23545;&#35937;&#12290; <code>Y*</code> &#24517;&#39035;&#21487;&#36716;&#25442;&#20026; <code>T*</code> &#12290;&#26500;&#36896;&#21518;&#65292; <code>r</code> &#20026;&#31354;&#12290;</div>
<div class="t-li1"><span class="t-li">13)</span> &#26500;&#36896; <code>shared_ptr</code> &#65292;&#31649;&#29702;&#24403;&#21069;&#20026; <code>r</code> &#25152;&#31649;&#29702;&#30340;&#23545;&#35937;&#12290;&#23384;&#20648;&#19982; <code>r</code> &#20851;&#32852;&#30340;&#21024;&#38500;&#22120;&#20197;&#22312;&#26410;&#26469;&#21024;&#38500;&#34987;&#31649;&#29702;&#23545;&#35937;&#12290;&#35843;&#29992;&#21518; <code>r</code> &#19981;&#31649;&#29702;&#23545;&#35937;&#12290;
<table class="t-rev-begin">
<tr class="t-rev t-since-cxx17">
<td>&#33509; <code>std::unique_ptr&lt;Y, Deleter&gt;::pointer</code> &#19981;<i>&#20860;&#23481;</i> <code>T*</code> &#21017;&#27492;&#37325;&#36733;&#19981;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;&#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp">r.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span></span></span> &#26159;&#31354;&#25351;&#38024;&#65292;&#21017;&#27492;&#37325;&#36733;&#31561;&#20215;&#20110;&#40664;&#35748;&#26500;&#36896;&#20989;&#25968; <span class="t-v">(1)</span> &#12290;</td>
<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
</tr>
</table>
&#33509; <code>Deleter</code> &#26159;&#24341;&#29992;&#31867;&#22411;&#65292;&#21017;&#31561;&#20215;&#20110; <span class="t-c"><span class="mw-geshi cpp source-cpp">shared_ptr<span class="br0">(</span>r.<span class="me1">release</span><span class="br0">(</span><span class="br0">)</span>, <a href="cpp-utility-functional-ref.html"><span class="kw1069">std::<span class="me2">ref</span></span></a><span class="br0">(</span>r.<span class="me1">get_deleter</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span> &#12290;&#21542;&#21017;&#65292;&#31561;&#20215;&#20110; <span class="t-c"><span class="mw-geshi cpp source-cpp">shared_ptr<span class="br0">(</span>r.<span class="me1">release</span><span class="br0">(</span><span class="br0">)</span>, std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span>r.<span class="me1">get_deleter</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="br0">)</span></span></span> &#12290;</div>
<p><code>T</code> &#19981;&#26159;&#25968;&#32452;&#31867;&#22411;&#26102;&#65292;&#37325;&#36733; <span class="t-v">(3)</span> &#12289; <span class="t-v">(4)</span> &#21450; <span class="t-v">(6)</span> &#20197; <code>ptr</code> &#21551;&#29992; <code>shared_from_this</code> &#65292;&#32780;&#37325;&#36733; <span class="t-v">(13)</span> &#20197; <span class="t-c"><span class="mw-geshi cpp source-cpp">r.<span class="me1">release</span><span class="br0">(</span><span class="br0">)</span></span></span> &#25152;&#36820;&#22238;&#30340;&#25351;&#38024;&#21551;&#29992; <code>shared_from_this</code> &#12290;</p>
<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">&#27880;&#35299;</span></h3>
<p><code>T</code> &#19981;&#26159;&#25968;&#32452;&#31867;&#22411;&#26159;&#65292;&#37325;&#36733; <span class="t-v">(3)</span> &#12289; <span class="t-v">(4)</span> &#21450; <span class="t-v">(6)</span> &#20197; <code>ptr</code> &#21551;&#29992; shared_from_this &#65292;&#32780;&#37325;&#36733; <span class="t-v">(13)</span> &#20197; <span class="t-c"><span class="mw-geshi cpp source-cpp">r.<span class="me1">release</span><span class="br0">(</span><span class="br0">)</span></span></span> &#25152;&#36820;&#22238;&#30340;&#25351;&#38024;&#21551;&#29992; shared_from_this &#12290;</p>
<p>&#26500;&#36896;&#20989;&#25968;&#20197; <code>U*</code> &#31867;&#22411;&#25351;&#38024; <code>ptr</code> <i>&#21551;&#29992; <code>shared_from_this</code></i> &#65292;&#34920;&#31034;&#23427;&#30830;&#23450; <code>U</code> &#26159;&#21542;&#25317;&#26377;&#20316;&#20026; <span class="t-lc"><a href="cpp-memory-enable_shared_from_this.html">std::enable_shared_from_this</a></span> &#29305;&#21270;&#30340;<span class="t-rev-inl t-since-cxx17"><span>&#26080;&#27495;&#20041;&#19988;&#21487;&#35775;&#38382;</span> <span><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></span></span>&#22522;&#31867;&#65292;&#32780;&#33509;&#22914;&#27492;&#65292;&#21017;&#26500;&#36896;&#20989;&#25968;&#27714;&#20540;&#35813;&#35821;&#21477;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="cpp source-cpp">
<pre class="de1"><span class="kw1">if</span> <span class="br0">(</span>ptr <span class="sy3">!</span><span class="sy1">=</span> nullptr <span class="sy3">&amp;&amp;</span> ptr<span class="sy2">-</span><span class="sy1">&gt;</span>weak_this.<span class="me1">expired</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span>
ptr<span class="sy2">-</span><span class="sy1">&gt;</span>weak_this <span class="sy1">=</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">&lt;</span><a href="cpp-types-remove_cv.html"><span class="kw597">std::<span class="me2">remove_cv_t</span></span></a><span class="sy1">&lt;</span>U<span class="sy1">&gt;&gt;</span><span class="br0">(</span><span class="sy2">*</span>this,
<span class="kw1">const_cast</span><span class="sy1">&lt;</span><a href="cpp-types-remove_cv.html"><span class="kw597">std::<span class="me2">remove_cv_t</span></span></a><span class="sy1">&lt;</span>U<span class="sy1">&gt;</span><span class="sy2">*</span><span class="sy1">&gt;</span><span class="br0">(</span>ptr<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span></pre></div>
</div>
<p>&#20854;&#20013; <code>weak_this</code> &#26159; <span class="t-lc">std::shared_from_this</span> &#30340;&#38544;&#34255; mutable <code>std::weak_ptr</code> &#25104;&#21592;&#12290;&#23545; <code>weak_this</code> &#25104;&#21592;&#30340;&#36171;&#20540;&#19981;&#26159;&#21407;&#23376;&#30340;&#65292;&#19988;&#19982;&#20219;&#20309;&#21040;&#21516;&#19968;&#23545;&#35937;&#30340;&#28508;&#22312;&#24182;&#21457;&#35775;&#38382;&#20914;&#31361;&#12290;&#36825;&#30830;&#20445;&#23558;&#26469;&#23545; <a href="cpp-memory-enable_shared_from_this-shared_from_this.html"><tt>shared_from_this()</tt></a> &#35843;&#29992;&#65292;&#23558;&#19982;&#27492;&#35064;&#25351;&#38024;&#26500;&#36896;&#20989;&#25968;&#25152;&#21019;&#24314;&#30340; <code>shared_ptr</code> &#20849;&#20139;&#25152;&#26377;&#26435;&#12290;</p>
<p>&#19978;&#36848;&#35299;&#37322;&#20195;&#30721;&#20013;&#65292;&#27979;&#35797; <code>ptr-&gt;weak_this.expired()</code> &#26159;&#20026;&#30830;&#20445;&#33509; <code>weak_this</code> &#25351;&#31034;&#24050;&#26377;&#21344;&#26377;&#32773;&#21017;&#37325;&#36171;&#20540;&#23427;&#12290;&#20174; C++17 &#36215;&#35201;&#27714;&#27492;&#27979;&#35797;&#12290;</p>
<p>&#35064;&#25351;&#38024;&#37325;&#36733;&#35748;&#23450;&#34987;&#25351;&#21521;&#23545;&#35937;&#30340;&#25152;&#26377;&#26435;&#12290;&#20174;&#32780;&#65292;&#29992;&#35064;&#25351;&#38024;&#37325;&#36733;&#20026;&#24050;&#32463;&#20026; <code>shared_ptr</code> &#25152;&#31649;&#29702;&#23545;&#35937;&#26500;&#36896; <code>shared_ptr</code> &#65292;&#20363;&#22914;&#20197; <span class="t-c"><span class="mw-geshi cpp source-cpp">shared_ptr<span class="br0">(</span>ptr.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span> &#24456;&#21487;&#33021;&#23548;&#33268;&#26410;&#23450;&#20041;&#34892;&#20026;&#65292;&#21363;&#20351;&#23545;&#35937;&#26377;&#23548;&#20986;&#33258; <span class="t-lc"><a href="cpp-memory-enable_shared_from_this.html">std::enable_shared_from_this</a></span> &#30340;&#31867;&#22411;&#12290;</p>
<p>&#22240;&#20026;&#40664;&#35748;&#26500;&#36896;&#20989;&#25968;&#26159; <code>constexpr</code> &#65292;&#38745;&#24577; shared_ptrs &#20316;&#20026;<a href="cpp-language-initialization.html#.E9.9D.9E.E5.B1.80.E9.83.A8.E5.8F.98.E9.87.8F">&#38745;&#24577;&#38750;&#23616;&#37096;&#21021;&#22987;&#21270;</a>&#30340;&#19968;&#37096;&#20998;&#21021;&#22987;&#21270;&#65292;&#22312;&#20219;&#20309;&#21160;&#24577;&#21021;&#22987;&#21270;&#24320;&#22987;&#21069;&#12290;&#36825;&#20351;&#24471;&#22312;&#20219;&#20309;&#38745;&#24577;&#23545;&#35937;&#30340;&#26500;&#36896;&#20989;&#25968;&#20013;&#20351;&#29992; shared_ptr &#26159;&#23433;&#20840;&#30340;&#12290;</p>
<p>C++11 &#21644; C++14 &#20013;&#65292;&#20174; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-memory-unique_ptr.html"><span class="kw733">std::<span class="me2">unique_ptr</span></span></a><span class="sy1">&lt;</span>T<span class="br0">[</span><span class="br0">]</span><span class="sy1">&gt;</span></span></span> &#26500;&#36896; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">&lt;</span>T<span class="sy1">&gt;</span></span></span> &#26159;&#21512;&#27861;&#30340;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="cpp source-cpp">
<pre class="de1"><a href="cpp-memory-unique_ptr.html"><span class="kw733">std::<span class="me2">unique_ptr</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="br0">[</span><span class="br0">]</span><span class="sy1">&gt;</span> arr<span class="br0">(</span>new <span class="kw4">int</span><span class="br0">[</span><span class="nu0">1</span><span class="br0">]</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="sy1">&gt;</span> ptr<span class="br0">(</span>std<span class="sy4">::</span><span class="me2">move</span><span class="br0">(</span>arr<span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span></pre></div>
</div>
<p>&#22240;&#20026; <code>shared_ptr</code> &#20174; <code>unique_ptr</code> &#33719;&#24471;&#20854;&#21024;&#38500;&#22120;&#65288; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-memory-default_delete.html"><span class="kw746">std::<span class="me2">default_delete</span></span></a><span class="sy1">&lt;</span>T<span class="br0">[</span><span class="br0">]</span><span class="sy1">&gt;</span></span></span> &#23545;&#35937;&#65289;&#65292;&#25925;&#33021;&#27491;&#30830;&#35299;&#20998;&#37197;&#25968;&#32452;&#12290;</p>
<p>C++17 &#20013;&#36825;&#19981;&#20877;&#21463;&#20801;&#35768;&#12290;&#24212;&#24403;&#20351;&#29992;&#26367;&#20195;&#30340;&#25968;&#32452;&#24418;&#24335; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">&lt;</span>T<span class="br0">[</span><span class="br0">]</span><span class="sy1">&gt;</span></span></span> &#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
<table class="t-par-begin">
<tr class="t-par">
<td>ptr</td>
<td>-</td>
<td>&#25351;&#21521;&#35201;&#31649;&#29702;&#30340;&#23545;&#35937;&#30340;&#25351;&#38024;</td>
</tr>
<tr class="t-par">
<td>d</td>
<td>-</td>
<td>&#29992;&#20110;&#38144;&#27585;&#23545;&#35937;&#30340;&#21024;&#38500;&#22120;</td>
</tr>
<tr class="t-par">
<td>alloc</td>
<td>-</td>
<td>&#29992;&#20110;&#20998;&#37197;&#20869;&#37096;&#20351;&#29992;&#30340;&#25968;&#25454;&#30340;&#20998;&#37197;&#22120;</td>
</tr>
<tr class="t-par">
<td>r</td>
<td>-</td>
<td>&#35201;&#20849;&#20139;&#25152;&#26377;&#26435;&#25110;&#20174;&#23427;&#33719;&#24471;&#25152;&#26377;&#26435;&#30340;&#21478;&#19968;&#26234;&#33021;&#25351;&#38024;</td>
</tr>
</table>
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">&#24322;&#24120;</span></h3>
<div class="t-li1"><span class="t-li">3)</span> &#33509;&#26080;&#27861;&#33719;&#24471;&#35201;&#27714;&#30340;&#38468;&#21152;&#20869;&#23384;&#21017;&#20026; <span class="t-lc"><a href="cpp-memory-new-bad_alloc.html">std::bad_alloc</a></span> &#12290;&#21487;&#33021;&#22240;&#20854;&#20182;&#38169;&#35823;&#25243;&#20986;&#23454;&#29616;&#23450;&#20041;&#30340;&#24322;&#24120;&#12290;&#33509;&#24322;&#24120;&#20986;&#29616;&#65292;&#21017;&#35843;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">delete ptr</span></span><span class="t-rev-inl t-since-cxx17"><span>&#65292;&#33509; <code>T</code> &#38750;&#25968;&#32452;&#31867;&#22411;&#65292;&#21542;&#21017;&#35843;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">delete<span class="br0">[</span><span class="br0">]</span> ptr</span></span></span> <span><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">4-7)</span> &#33509;&#26080;&#27861;&#33719;&#24471;&#35201;&#27714;&#30340;&#38468;&#21152;&#20869;&#23384;&#21017;&#20026; <span class="t-lc"><a href="cpp-memory-new-bad_alloc.html">std::bad_alloc</a></span> &#12290;&#21487;&#33021;&#22240;&#20854;&#20182;&#38169;&#35823;&#25243;&#20986;&#23454;&#29616;&#23450;&#20041;&#30340;&#24322;&#24120;&#12290;&#33509;&#24322;&#24120;&#20986;&#29616;&#65292;&#21017;&#35843;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">d<span class="br0">(</span>ptr<span class="br0">)</span></span></span> &#12290;</div>
<div class="t-li1"><span class="t-li">11)</span> &#33509; <span class="t-c"><span class="mw-geshi cpp source-cpp">r.<span class="me1">expired</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">==</span> <span class="kw2">true</span></span></span> &#21017;&#20026; <span class="t-lc"><a href="cpp-memory-bad_weak_ptr.html">std::bad_weak_ptr</a></span> &#12290;&#33509;&#24322;&#24120;&#20986;&#29616;&#65292;&#21017;&#27492;&#26500;&#36896;&#20989;&#25968;&#26080;&#25928;&#26524;&#12290;</div>
<div class="t-li1"><span class="t-li">12)</span> &#33509;&#26080;&#27861;&#33719;&#24471;&#35201;&#27714;&#30340;&#38468;&#21152;&#20869;&#23384;&#21017;&#20026; <span class="t-lc"><a href="cpp-memory-new-bad_alloc.html">std::bad_alloc</a></span> &#12290;&#21487;&#33021;&#22240;&#20854;&#20182;&#38169;&#35823;&#25243;&#20986;&#23454;&#29616;&#23450;&#20041;&#30340;&#24322;&#24120;&#12290;&#33509;&#24322;&#24120;&#20986;&#29616;&#65292;&#21017;&#27492;&#26500;&#36896;&#20989;&#25968;&#26080;&#25928;&#26524;&#12290;</div>
<div class="t-li1"><span class="t-li">13)</span> &#33509;&#25243;&#24322;&#24120;&#65292;&#21017;&#26500;&#36896;&#20989;&#25968;&#26080;&#25928;&#26524;&#12290;</div>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
<div class="t-example">
<div class="t-example-live-link"></div>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="cpp source-cpp">
<pre class="de1"><span class="co2">#include &lt;memory&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="kw1">struct</span> Foo <span class="br0">{</span>
Foo<span class="br0">(</span><span class="br0">)</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">&lt;&lt;</span> <span class="st0">&quot;Foo...<span class="es1">\n</span>&quot;</span><span class="sy4">;</span> <span class="br0">}</span>
~Foo<span class="br0">(</span><span class="br0">)</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">&lt;&lt;</span> <span class="st0">&quot;~Foo...<span class="es1">\n</span>&quot;</span><span class="sy4">;</span> <span class="br0">}</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="kw1">struct</span> D <span class="br0">{</span>
<span class="kw4">void</span> operator<span class="br0">(</span><span class="br0">)</span><span class="br0">(</span>Foo<span class="sy2">*</span> p<span class="br0">)</span> <span class="kw4">const</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">&lt;&lt;</span> <span class="st0">&quot;Call delete from function object...<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
delete p<span class="sy4">;</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="br0">{</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;constructor with no managed object<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">&lt;</span>Foo<span class="sy1">&gt;</span> sh1<span class="sy4">;</span>
<span class="br0">}</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">&lt;&lt;</span> <span class="st0">&quot;constructor with object<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">&lt;</span>Foo<span class="sy1">&gt;</span> sh2<span class="br0">(</span>new Foo<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">&lt;</span>Foo<span class="sy1">&gt;</span> sh3<span class="br0">(</span>sh2<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">&lt;&lt;</span> sh2.<span class="me1">use_count</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>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> sh3.<span class="me1">use_count</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>
<span class="br0">{</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;constructor with object and deleter<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">&lt;</span>Foo<span class="sy1">&gt;</span> sh4<span class="br0">(</span>new Foo, D<span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">&lt;</span>Foo<span class="sy1">&gt;</span> sh5<span class="br0">(</span>new Foo, <span class="br0">[</span><span class="br0">]</span><span class="br0">(</span><span class="kw4">auto</span> p<span class="br0">)</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">&lt;&lt;</span> <span class="st0">&quot;Call delete from lambda...<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
delete p<span class="sy4">;</span>
<span class="br0">}</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="br0">}</span></pre></div>
</div>
<p>&#36755;&#20986;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="text source-text">
<pre class="de1">constructor with no managed object
constructor with object
Foo...
2
2
~Foo...
constructor with object and deleter
Foo...
Foo...
Call delete from lambda...
~Foo...
Call delete from function object...
~Foo..</pre></div>
</div>
</div>
<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">&#32570;&#38519;&#25253;&#21578;</span></h3>
<p>&#19979;&#21015;&#26356;&#25913;&#34892;&#20026;&#30340;&#32570;&#38519;&#25253;&#21578;&#36861;&#28335;&#22320;&#24212;&#29992;&#20110;&#20197;&#21069;&#20986;&#29256;&#30340; C++ &#26631;&#20934;&#12290;</p>
<table class="dsctable" style="font-size:0.8em">
<tr>
<th>DR</th>
<th>&#24212;&#29992;&#20110;</th>
<th>&#20986;&#29256;&#26102;&#30340;&#34892;&#20026;</th>
<th>&#27491;&#30830;&#34892;&#20026;</th>
</tr>
<tr>
<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue3548">LWG 3548</a></td>
<td>C++11</td>
<td>&#28304;&#33258; <code>unique_ptr</code> &#30340;&#26500;&#36896;&#20989;&#25968;&#22797;&#21046;&#26500;&#36896;&#21024;&#38500;&#22120;</td>
<td>&#25913;&#20026;&#31227;&#21160;&#26500;&#36896;</td>
</tr>
</table>
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
<table class="t-dsc-begin">
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-memory-shared_ptr-make_shared.html"><span class="t-lines"><span>make_shared</span><span>make_shared_for_overwrite</span></span></a></div>
<div><span class="t-lines"><span></span><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#21019;&#24314;&#31649;&#29702;&#19968;&#20010;&#26032;&#23545;&#35937;&#30340;&#20849;&#20139;&#25351;&#38024;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-memory-shared_ptr-allocate_shared.html"><span class="t-lines"><span>allocate_shared</span><span>allocate_shared_for_overwrite</span></span></a></div>
<div><span class="t-lines"><span></span><span><span class="t-mark-rev t-since-cxx20">(C++20)</span></span></span></div>
</div>
</td>
<td>&#21019;&#24314;&#31649;&#29702;&#19968;&#20010;&#29992;&#20998;&#37197;&#22120;&#20998;&#37197;&#30340;&#26032;&#23545;&#35937;&#30340;&#20849;&#20139;&#25351;&#38024;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
</tr>
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-memory-enable_shared_from_this.html"><span class="t-lines"><span>enable_shared_from_this</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
</div>
</td>
<td>&#20801;&#35768;&#23545;&#35937;&#21019;&#24314;&#25351;&#20195;&#33258;&#36523;&#30340; <code>shared_ptr</code><br />
<span class="t-mark">(&#31867;&#27169;&#26495;)</span></td>
</tr>
</table>
</div>
<div class="visualClear"></div>
</div>
</div>
</div>
</body>
</html>
Reference in New Issue View Git Blame Copy Permalink