---
title: 子选择器
slug: Web/CSS/Child_combinator
tags:
  - CSS
  - Selectors
translation_of: Web/CSS/Child_combinator
---
<p>{{ CSSRef() }}</p>

<h2 id="Summary" name="Summary">概述</h2>

<p>当使用  <code>&gt;</code> 选择符分隔两个元素时,它只会匹配那些作为第一个元素的<strong>直接后代<span style="line-height: 21px;">(</span></strong><span style="line-height: inherit;">子元素)的第二元素. 与之相比, 当两个元素由 </span><a href="/en/CSS/Descendant_selectors" style="line-height: inherit;" title="https://developer.mozilla.org/en/CSS/Descendant_selectors">后代选择器 </a>相连时<span style="line-height: inherit;">, 它表示匹配存在的所有由第一个元素作为祖先元素(但不一定是父元素)的第二个元素, 无论它在 DOM 中"跳跃" 多少次.</span></p>

<h2 id="Syntax" name="Syntax">语法</h2>

<pre class="eval">元素1 &gt; 元素2 {<em>样式声明</em> }
</pre>

<h2 id="Examples" name="Examples">示例</h2>

<pre class="brush: css">span { background-color: white; }
div &gt; span {
  background-color: DodgerBlue;
}
</pre>

<p>当应用与如下标记时:</p>

<pre class="brush: html">&lt;div&gt;
  &lt;span&gt;Span 1. In the div.
    &lt;span&gt;Span 2. In the span that's in the div.&lt;/span&gt;
  &lt;/span&gt;
&lt;/div&gt;
&lt;span&gt;Span 3. Not in a div at all&lt;/span&gt;
</pre>

<p>会得到下面的效果:</p>

<p style="margin-left: 40px;"><span style="background-color: DodgerBlue;">Span 1. In the div.</span> <span>Span 2. In the span that's in the div.</span><br>
 <span>Span 3. Not in a div at all.</span></p>

<h2 id="Specifications" name="Specifications">规范</h2>

<table class="standard-table">
 <thead>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
 </thead>
 <tbody>
  <tr>
   <td><a class="external" href="http://www.w3.org/TR/css3-selectors/#child-combinators">CSS Selectors Level 3</a></td>
   <td>{{ Spec2('CSS3 Selectors') }}</td>
   <td> </td>
  </tr>
  <tr>
   <td><a class="external" href="http://www.w3.org/TR/CSS21/selector.html#child-selectors">CSS 2.1</a></td>
   <td>{{ Spec2('CSS2.1') }}</td>
   <td> </td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>

{{Compat("css.selectors.child")}}

<h2 id="相关">相关</h2>