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:first-childCSS當中的一種偽類別(pseudo-class),代表任何身為長子的元素(親元素的第一個子元素)。

語法

:first-child

範例

範例 1

HTML 內文

<div>
  <span>This span is limed!</span>
  <span>This span is not. :(</span>
</div>

CSS 內文

span:first-child {
    background-color: lime;
}

呈現效果如下:

範例 2 - 使用 UL

HTML 內文

<ul>
  <li>List 1</li>
  <li>List 2</li>
  <li>List 3</li>
</ul>

CSS 內文

li{
  color:red;
}
li:first-child{
  color:green;
}

呈現效果如下:

規格

規格 狀態 註解
Selectors Level 4
The definition of ':first-child' in that specification.
Working Draft 無變更
Selectors Level 3
The definition of ':first-child' in that specification.
Recommendation 無變更
CSS Level 2 (Revision 1)
The definition of ':first-child' in that specification.
Recommendation 初始定義

瀏覽器相容性

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

功能 Chrome Firefox (Gecko) Internet Explorer Opera Safari
基礎支援 4.0 3.0 (1.9) 7[1] 9.5 4
功能 Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
基礎支援 1.0 1.0 (1.9.1) 7[1] 10.0 3.1

[1] 在不重新載入網頁的情況下,Internet Explorer 7 的樣式表並不會套用在動態新增的元素上。在 Internet Explorer 8,若元素是以點擊連結而形成的,則 first-child 在該連結不被選取後才有作用。

參見

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最近更新: mgrn,