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<title>std::chrono::time_point&lt;Clock,Duration&gt;::time_point</title>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::chrono::time_point&lt;Clock,Duration&gt;::</span>time_point</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-chrono.html">chrono</a>&lrm; | <a href="cpp-chrono-time_point.html">time point</a></span></div>
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<td rowspan="142">(1)</td>
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<div><span class="mw-geshi cpp source-cpp">time_point<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span><br />
<span class="t-mark-rev t-until-cxx14">(C++14 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> time_point<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 &#36215;)</span></td>
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<td rowspan="142">(2)</td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">explicit</span> time_point<span class="br0">(</span> <span class="kw4">const</span> duration<span class="sy3">&amp;</span> d <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span><br />
<span class="t-mark-rev t-until-cxx14">(C++14 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">constexpr</span> <span class="kw1">explicit</span> time_point<span class="br0">(</span> <span class="kw4">const</span> duration<span class="sy3">&amp;</span> d <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 &#36215;)</span></td>
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<td rowspan="142">(3)</td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Duration2 <span class="sy1">&gt;</span><br />
time_point<span class="br0">(</span> <span class="kw4">const</span> time_point<span class="sy1">&lt;</span>Clock,Duration2<span class="sy1">&gt;</span><span class="sy3">&amp;</span> t <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span><br />
<span class="t-mark-rev t-until-cxx14">(C++14 &#21069;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Duration2 <span class="sy1">&gt;</span><br />
<span class="kw4">constexpr</span> time_point<span class="br0">(</span> <span class="kw4">const</span> time_point<span class="sy1">&lt;</span>Clock,Duration2<span class="sy1">&gt;</span><span class="sy3">&amp;</span> t <span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx14">(C++14 &#36215;)</span></td>
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<p>&#20174;&#25968;&#20010;&#21487;&#36873;&#25968;&#25454;&#28304;&#20043;&#19968;&#26500;&#36896;&#26032;&#30340; <code>time_point</code> &#12290;</p>
<div class="t-li1"><span class="t-li">1)</span> &#40664;&#35748;&#26500;&#36896;&#20989;&#25968;&#65292;&#21019;&#24314;&#34920;&#31034; <code>Clock</code> &#30340;&#32426;&#20803;&#65288;&#21363; <span class="t-lc"><a href="cpp-chrono-time_point-time_since_epoch.html">time_since_epoch()</a></span> &#20026;&#38646;&#65289;&#30340; <code>time_point</code> &#12290;</div>
<div class="t-li1"><span class="t-li">2)</span> &#26500;&#36896;&#20301;&#20110; <code>Clock</code> &#30340;&#32426;&#20803;&#21152;&#19978; <code>d</code> &#30340; <code>time_point</code> &#12290;</div>
<div class="t-li1"><span class="t-li">3)</span> &#36890;&#36807;&#36716;&#25442; <code>t</code> &#20026; <code>duration</code> &#26500;&#36896; <code>time_point</code> &#12290;&#27492;&#26500;&#36896;&#20989;&#25968;&#20165;&#33509; <code>Duration2</code> &#21487;&#38544;&#24335;&#36716;&#25442;&#20026; <code>duration</code> &#25165;&#21442;&#19982;&#37325;&#36733;&#20915;&#35758;&#12290;</div>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>d</td>
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<td>&#22797;&#21046;&#26469;&#28304;&#30340; <code>duration</code></td>
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<td>t</td>
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<td>&#36716;&#25442;&#26469;&#28304;&#30340; <code>time_point</code></td>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
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<pre class="de1"><span class="co2">#include &lt;chrono&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="kw1">using</span> Clock <span class="sy1">=</span> <a href="cpp-chrono-high_resolution_clock.html"><span class="kw1008">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">high_resolution_clock</span></span></a><span class="sy4">;</span>
<span class="kw1">using</span> TimePoint <span class="sy1">=</span> <a href="cpp-chrono-time_point.html"><span class="kw991">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">time_point</span></span></a><span class="sy1">&lt;</span>Clock<span class="sy1">&gt;</span><span class="sy4">;</span>
<span class="kw4">void</span> print_ms<span class="br0">(</span><span class="kw4">const</span> TimePoint<span class="sy3">&amp;</span> point<span class="br0">)</span>
<span class="br0">{</span>
<span class="kw1">using</span> Ms <span class="sy1">=</span> <a href="cpp-chrono-duration.html"><span class="kw996">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">milliseconds</span></span></a><span class="sy4">;</span>
<span class="kw4">const</span> Clock<span class="sy4">::</span><span class="me2">duration</span> since_epoch <span class="sy1">=</span> point.<span class="me1">time_since_epoch</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">&lt;&lt;</span> <a href="cpp-chrono-duration-duration_cast.html"><span class="kw1000">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">duration_cast</span></span></a><span class="sy1">&lt;</span>Ms<span class="sy1">&gt;</span><span class="br0">(</span>since_epoch<span class="br0">)</span>.<span class="me1">count</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot; ms<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="kw4">const</span> TimePoint default_value <span class="sy1">=</span> TimePoint<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// (1)</span>
print_ms<span class="br0">(</span>default_value<span class="br0">)</span><span class="sy4">;</span> <span class="co1">// 0 ms</span>
<span class="kw4">const</span> Clock<span class="sy4">::</span><span class="me2">duration</span> duration_4_seconds <span class="sy1">=</span> <a href="cpp-chrono-duration.html"><span class="kw997">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">seconds</span></span></a><span class="br0">(</span><span class="nu0">4</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">const</span> TimePoint time_point_4_seconds<span class="br0">(</span>duration_4_seconds<span class="br0">)</span><span class="sy4">;</span> <span class="co1">// (2)</span>
<span class="co1">// &#20174;&#32426;&#20803;&#24320;&#22987; 4 &#31186;</span>
print_ms<span class="br0">(</span>time_point_4_seconds<span class="br0">)</span><span class="sy4">;</span> <span class="co1">// 4000 ms</span>
<span class="kw4">const</span> TimePoint time_point_now <span class="sy1">=</span> Clock<span class="sy4">::</span><span class="me2">now</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// (3)</span>
print_ms<span class="br0">(</span>time_point_now<span class="br0">)</span><span class="sy4">;</span> <span class="co1">// 43098276 ms</span>
<span class="br0">}</span></pre></div>
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<p>&#21487;&#33021;&#30340;&#36755;&#20986;&#65306;</p>
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<pre class="de1">0 ms
4000 ms
43098276 ms</pre></div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
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<div><a href="cpp-chrono-duration-duration.html"><span class="t-lines"><span>(&#26500;&#36896;&#20989;&#25968;)</span></span></a></div>
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<td>&#26500;&#36896;&#26032; duration<br />
<span class="t-mark">(<code>std::chrono::duration&lt;Rep,Period&gt;</code> &#30340;&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-chrono-duration-duration_cast.html"><span class="t-lines"><span>duration_cast</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
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<td>&#36716;&#25442;&#26102;&#38271;&#21040;&#21478;&#19968;&#20010;&#25317;&#26377;&#19981;&#21516;&#22016;&#21970;&#38388;&#38548;&#30340;&#26102;&#38271;<br />
<span class="t-mark">(&#20989;&#25968;&#27169;&#26495;)</span></td>
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