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本文档使用
php.cn手册 发布
文字
语法：
Selector { sRule!important; }
说明：
提升指定样式规则的应用优先权。
IE6及以下浏览器有个比较显式的支持问题存在，!important在同一条规则集里不生效。请看下述代码：
示例代码：
div { color: #f00 !important; color: #000; }
在上述代码中，IE6及以下浏览器div的文本颜色为#000，!important并没有覆盖后面的规则；其它浏览器下div的文本颜色为#f00
IE6及以下浏览器要使!important生效，可用以下代码：
示例代码：
div { color: #f00 !important; color: #000; }在上述代码中，IE6及以下浏览器中div的文本颜色表现与其它浏览器一致，都为#f00
兼容性：
| IE | Firefox | Chrome | Safari | Opera | iOS Safari | Android Browser | Android Chrome |
|---|---|---|---|---|---|---|---|
| 6.0 #1 | 2.0+ | 4.0+ | 3.1+ | 3.5+ | 3.2+ | 2.1+ | 18.0+ |
| 7.0+ |
IE6及更早浏览器下，!important在同一条规则集内不生效。
示例：
实例
<!DOCTYPE html>
<html lang="zh-cmn-Hans">
<head>
<meta charset="utf-8" />
<title>!important_CSS参考手册_web前端开发参考手册系列</title>
<meta name="author" content="Joy Du(飘零雾雨), dooyoe@gmail.com, www.doyoe.com" />
<style>
.test {
color: #f00 !important;
color: #000;
}
.test2 {
color: #f00 !important;
}
.test2 {
color: #000;
}
</style>
</head>
<body>
<div class="test">同一条样式内，!important将在IE6及以下浏览器中失效</div>
<div class="test2">在分散的样式条目内，IE6及以下浏览器对!important的支持与其它浏览器一致</div>
</body>
</html> 运行实例 »
点击 "运行实例" 按钮查看在线实例