2019-04-21 11:50:48 +08:00

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<article id="wikiArticle">
<p></p><p></p>
<p><code><strong>pop()</strong></code>方法从数组中删除最后一个元素,并返回该元素的值。此方法更改数组的长度。</p>
<div><iframe class="interactive interactive-js" frameborder="0" height="250" src="https://interactive-examples.mdn.mozilla.net/pages/js/array-pop.html" width="100%"></iframe></div>
<p class="hidden">The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone <a class="external" href="https://github.com/mdn/interactive-examples" rel="noopener">https://github.com/mdn/interactive-examples</a> and send us a pull request.</p>
<h2 id="Syntax" name="Syntax">语法</h2>
<pre><code class="language-javascript"><code><em>arr</em>.pop()</code></code></pre>
<h3 id="返回值">返回值</h3>
<p>从数组中删除的元素(当数组为空时返回<a href="Reference/Global_Objects/undefined" title="undefined是全局对象的一个属性。也就是说它是全局作用域的一个变量。undefined的最初值就是原始数据类型undefined。"><code>undefined</code></a>)。</p>
<h2 id="Description" name="Description">描述</h2>
<p><code>pop</code> 方法从一个数组中删除并返回最后一个元素。</p>
<p><code>pop</code> 方法有意具有通用性。该方法和 <a href="Reference/Global_Objects/Function/call" title="call() 方法调用一个函数, 其具有一个指定的this值和分别地提供的参数(参数的列表)。"><code>call()</code></a><a href="Reference/Global_Objects/Function/apply" title="apply() 方法调用一个具有给定this值的函数以及作为一个数组或类似数组对象提供的参数。"><code>apply()</code></a> 一起使用时,可应用在类似数组的对象上。<code>pop</code>方法根据 <code>length</code>属性来确定最后一个元素的位置。如果不包含<code>length</code>属性或<code>length</code>属性不能被转成一个数值,会将<code>length</code>置为0并返回<code>undefined</code></p>
<p>如果你在一个空数组上调用 pop(),它返回  <a href="Reference/Global_Objects/undefined" title="undefined是全局对象的一个属性。也就是说它是全局作用域的一个变量。undefined的最初值就是原始数据类型undefined。"><code>undefined</code></a></p>
<h2 id="Example" name="Example">示例</h2>
<h3 id="Example:_Removing_the_last_element_of_an_array" name="Example:_Removing_the_last_element_of_an_array">例子: 删除掉数组的最后一个元素</h3>
<p>下面的代码首先创建了一个拥有四个元素的数组 myFish然后删除掉它的最后一个元素。</p>
<pre><code class="language-js">let myFish = ["angel", "clown", "mandarin", "surgeon"];
let popped = myFish.pop();
console.log(myFish);
// ["angel", "clown", "mandarin"]
console.log(popped);
// surgeon
</code></pre>
<h2 id="规范" style="margin-bottom: 20px; line-height: 30px;">规范</h2>
<table>
<tbody>
<tr>
<th scope="col">Specification</th>
<th scope="col">Status</th>
<th scope="col">Comment</th>
</tr>
<tr>
<td><a class="external" href="https://www.ecma-international.org/publications/files/ECMA-ST-ARCH/ECMA-262,%203rd%20edition,%20December%201999.pdf" hreflang="en" lang="en" rel="noopener" title="ECMAScript 3rd Edition (ECMA-262)">ECMAScript 3rd Edition (ECMA-262)</a></td>
<td><span class="spec-Standard">Standard</span></td>
<td>Initial definition. Implemented in JavaScript 1.2.</td>
</tr>
<tr>
<td><a class="external" href="https://www.ecma-international.org/ecma-262/5.1/#sec-15.4.4.6" hreflang="en" lang="en" rel="noopener">ECMAScript 5.1 (ECMA-262)<br/><small lang="zh-CN">Array.prototype.pop</small></a></td>
<td><span class="spec-Standard">Standard</span></td>
<td> </td>
</tr>
<tr>
<td><a class="external" href="https://www.ecma-international.org/ecma-262/6.0/#sec-array.prototype.pop" hreflang="en" lang="en" rel="noopener">ECMAScript 2015 (6th Edition, ECMA-262)<br/><small lang="zh-CN">Array.prototype.pop</small></a></td>
<td><span class="spec-Standard">Standard</span></td>
<td> </td>
</tr>
<tr>
<td><a class="external" href="https://tc39.github.io/ecma262/#sec-array.prototype.pop" hreflang="en" lang="en" rel="noopener">ECMAScript Latest Draft (ECMA-262)<br/><small lang="zh-CN">Array.prototype.pop</small></a></td>
<td><span class="spec-Draft">Draft</span></td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="浏览器兼容性">浏览器兼容性</h2>
<div>
<div class="hidden">The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out <a class="external" href="https://github.com/mdn/browser-compat-data" rel="noopener">https://github.com/mdn/browser-compat-data</a> and send us a pull request.</div>
<p></p><div class="bc-data"><a class="bc-github-link external" href="https://github.com/mdn/browser-compat-data" rel="noopener">Update compatibility data on GitHub</a><table class="bc-table bc-table-js"><thead><tr class="bc-platforms"><td></td><th class="bc-platform-desktop" colspan="6"><span>Desktop</span></th><th class="bc-platform-mobile" colspan="7"><span>Mobile</span></th><th class="bc-platform-server" colspan="1"><span>Server</span></th></tr><tr class="bc-browsers"><td></td><th class="bc-browser-chrome"><span class="bc-head-txt-label bc-head-icon-chrome">Chrome</span></th><th class="bc-browser-edge"><span class="bc-head-txt-label bc-head-icon-edge">Edge</span></th><th class="bc-browser-firefox"><span class="bc-head-txt-label bc-head-icon-firefox">Firefox</span></th><th class="bc-browser-ie"><span class="bc-head-txt-label bc-head-icon-ie">Internet Explorer</span></th><th class="bc-browser-opera"><span class="bc-head-txt-label bc-head-icon-opera">Opera</span></th><th class="bc-browser-safari"><span class="bc-head-txt-label bc-head-icon-safari">Safari</span></th><th class="bc-browser-webview_android"><span class="bc-head-txt-label bc-head-icon-webview_android">Android webview</span></th><th class="bc-browser-chrome_android"><span class="bc-head-txt-label bc-head-icon-chrome_android">Chrome for Android</span></th><th class="bc-browser-edge_mobile"><span class="bc-head-txt-label bc-head-icon-edge_mobile">Edge Mobile</span></th><th class="bc-browser-firefox_android"><span class="bc-head-txt-label bc-head-icon-firefox_android">Firefox for Android</span></th><th class="bc-browser-opera_android"><span class="bc-head-txt-label bc-head-icon-opera_android">Opera for Android</span></th><th class="bc-browser-safari_ios"><span class="bc-head-txt-label bc-head-icon-safari_ios">Safari on iOS</span></th><th class="bc-browser-samsunginternet_android"><span class="bc-head-txt-label bc-head-icon-samsunginternet_android">Samsung Internet</span></th><th class="bc-browser-nodejs"><span class="bc-head-txt-label bc-head-icon-nodejs">Node.js</span></th></tr></thead><tbody><tr><th scope="row"><code>pop</code></th><td class="bc-supports-yes bc-browser-chrome"><span class="bc-browser-name">Chrome</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
1</td><td class="bc-supports-yes bc-browser-edge"><span class="bc-browser-name">Edge</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
12</td><td class="bc-supports-yes bc-browser-firefox"><span class="bc-browser-name">Firefox</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
1</td><td class="bc-supports-yes bc-browser-ie"><span class="bc-browser-name">IE</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
5.5</td><td class="bc-supports-yes bc-browser-opera"><span class="bc-browser-name">Opera</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
Yes</td><td class="bc-supports-yes bc-browser-safari"><span class="bc-browser-name">Safari</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
Yes</td><td class="bc-supports-yes bc-browser-webview_android"><span class="bc-browser-name">WebView Android</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
Yes</td><td class="bc-supports-yes bc-browser-chrome_android"><span class="bc-browser-name">Chrome Android</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
Yes</td><td class="bc-supports-yes bc-browser-edge_mobile"><span class="bc-browser-name">Edge Mobile</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
Yes</td><td class="bc-supports-yes bc-browser-firefox_android"><span class="bc-browser-name">Firefox Android</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
4</td><td class="bc-supports-yes bc-browser-opera_android"><span class="bc-browser-name">Opera Android</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
Yes</td><td class="bc-supports-yes bc-browser-safari_ios"><span class="bc-browser-name">Safari iOS</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
Yes</td><td class="bc-supports-yes bc-browser-samsunginternet_android"><span class="bc-browser-name">Samsung Internet Android</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
Yes</td><td class="bc-supports-yes bc-browser-nodejs"><span class="bc-browser-name">nodejs</span><abbr class="bc-level-yes only-icon" title="Full support">
<span>Full support</span>
</abbr>
Yes</td></tr></tbody></table><section class="bc-legend" id="sect1"><h3 class="offscreen" id="Legend">Legend</h3><dl><dt><span class="bc-supports-yes bc-supports">
<abbr class="bc-level bc-level-yes only-icon" title="Full support">
<span>Full support</span>
 
</abbr></span></dt><dd>Full support</dd></dl></section></div><p></p>
</div>
<h2 id="相关链接">相关链接</h2>
<ul>
<li><a href="Reference/Global_Objects/Array/push" title="push() 方法将一个或多个元素添加到数组的末尾,并返回该数组的新长度。"><code>Array.prototype.push()</code></a></li>
<li><a href="Reference/Global_Objects/Array/shift" title="shift() 方法从数组中删除第一个元素,并返回该元素的值。此方法更改数组的长度。"><code>Array.prototype.shift()</code></a></li>
<li><a href="Reference/Global_Objects/Array/unshift" title="unshift() 方法将一个或多个元素添加到数组的开头,并返回该数组的新长度。"><code>Array.prototype.unshift()</code></a></li>
<li><a href="Reference/Global_Objects/Array/concat" title="concat() 方法用于合并两个或多个数组。此方法不会更改现有数组,而是返回一个新数组。"><code>Array.prototype.concat()</code></a></li>
<li><a href="Reference/Global_Objects/Array/splice" title="splice() 方法通过删除或替换现有元素来修改数组,并以数组形式返回被修改的内容。此方法会改变原数组。"><code>Array.prototype.splice()</code></a></li>
</ul>
</article>