files/zh-cn/web/api/element/previouselementsibling/index.html


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---
title: NonDocumentTypeChildNode.previousElementSibling
slug: Web/API/Element/previousElementSibling
translation_of: Web/API/NonDocumentTypeChildNode/previousElementSibling
original_slug: Web/API/NonDocumentTypeChildNode/previousElementSibling
---
<p>{{ ApiRef() }}</p>

<h3 id="Summary" name="Summary">概述</h3>

<p><strong>previousElementSibling</strong> 返回当前元素在其父元素的子元素节点中的前一个元素节点,如果该元素已经是第一个元素节点,则返回<code>null,</code>该属性是只读的.</p>

<h3 id="Syntax_and_values" name="Syntax_and_values">语法</h3>

<pre class="eval">var <em>prevNode</em> = elementNodeReference.previousElementSibling;
</pre>

<h3 id="Example" name="Example">例子</h3>

<pre class="brush: html">&lt;div id="div-01"&gt;Here is div-01&lt;/div&gt;
&lt;div id="div-02"&gt;Here is div-02&lt;/div&gt;
&lt;li&gt;This is a list item&lt;/li&gt;
&lt;li&gt;This is another list item&lt;/li&gt;
&lt;div id="div-03"&gt;Here is div-03&lt;/div&gt;

&lt;script type="text/javascript"&gt;
  var el = document.getElementById('div-03').previousElementSibling;
  document.write('&lt;p&gt;Siblings of div-03&lt;/p&gt;&lt;ol&gt;');
  while (el) {
    document.write('&lt;li&gt;' + el.nodeName + '&lt;/li&gt;');
    el = el.previousElementSibling;
  }
  document.write('&lt;/ol&gt;');
&lt;/script&gt;
</pre>

<p>上面的例子会输出以下内容:</p>

<pre>Siblings of div-03

   1. LI
   2. LI
   3. DIV
   4. DIV
</pre>

<h3 id="Specification" name="Specification">浏览器兼容性</h3>

<p>{{ CompatibilityTable() }}</p>

<div id="compat-desktop">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Chrome</th>
   <th>Firefox (Gecko)</th>
   <th>Internet Explorer</th>
   <th>Opera</th>
   <th>Safari</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>4</td>
   <td>{{ CompatGeckoDesktop("1.9.1") }}</td>
   <td>9</td>
   <td>9.8</td>
   <td>4</td>
  </tr>
 </tbody>
</table>
</div>

<div id="compat-mobile">
<table class="compat-table" style="font-family: 'Open Sans Light', Helvetica, Arial, sans-serif; font-size: 16px; line-height: 16px;">
 <tbody>
  <tr>
   <th style="line-height: 16px;">Feature</th>
   <th style="line-height: 16px;">Android</th>
   <th style="line-height: 16px;">Firefox Mobile (Gecko)</th>
   <th style="line-height: 16px;">IE Mobile</th>
   <th style="line-height: 16px;">Opera Mobile</th>
   <th style="line-height: 16px;">Safari Mobile</th>
  </tr>
  <tr>
   <td>Basic support (on {{domxref("Element")}})</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatGeckoMobile("1.9.1")}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>9.8</td>
   <td>{{CompatVersionUnknown}}</td>
  </tr>
  <tr>
   <td>Support on {{domxref("CharacterData")}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatGeckoMobile("25")}}</td>
   <td>{{CompatNo}}</td>
   <td>16.0</td>
   <td>{{CompatNo}}</td>
  </tr>
 </tbody>
</table>
</div>

<h3 id="Specification" name="Specification">规范</h3>

<p><a class="external" href="http://www.w3.org/TR/2008/REC-ElementTraversal-20081222/#attribute-previousElementSibling">Element Traversal Specification: previousElementSibling</a></p>

<h3 id="相关链接">相关链接</h3>

<ul>
 <li><a class="internal" href="/zh-cn/DOM/Element.childElementCount" title="zh-cn/DOM/Element.childElementCount"><code>childElementCount</code></a></li>
 <li><a class="internal" href="/zh-cn/DOM/Element.children" title="zh-cn/DOM/Element.children"><code>children</code></a></li>
 <li><a class="internal" href="/zh-cn/DOM/Element.firstElementChild" title="zh-cn/DOM/Element.firstElementChild"><code>firstElementChild</code></a></li>
 <li><a class="internal" href="/zh-cn/DOM/Element.lastElementChild" title="zh-cn/DOM/Element.lastElementChild"><code>lastElementChild</code></a></li>
 <li><a class="internal" href="/zh-cn/DOM/Element.nextElementSibling" title="zh-cn/DOM/Element.nextElementSibling"><code>nextElementSibling</code></a></li>
</ul>

<p>{{ languages( {"en": "en/DOM/element.previousElementSibling" } ) }}</p>