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>

{{Compat("api.Element.previousElementSibling")}}