以前的兼容
<span>.transparent_class</span> <span>{
<span><span>-ms-filter</span>:<span><span>"progid:DXImageTransform.Microsoft.Alpha(Opacity=50)"</span>;</span></span> <span>/* ie8 */</span>
<span><span>filter</span>:<span><span>alpha(opacity=<span>50</span>)</span>;</span></span> <span>/* ie5-7 */</span>
<span><span>-moz-opacity</span>:<span><span>0.5</span>;</span></span> <span>/* old mozilla browser like netscape */</span>
<span><span>-khtml-opacity</span>:<span> <span>0.5</span>;</span></span> <span>/* for really really old safari */</span>
<span><span>opacity</span>:<span> <span>0.5</span>;</span></span> <span>/* css standard, currently it works in most modern browsers like firefox, */</span>
<span>}</span></span>
现在的兼容
<span>.transparent_class</span> <span>{
<span><span>-ms-filter</span>:<span><span>"progid:DXImageTransform.Microsoft.Alpha(Opacity=50)"</span>;</span></span> <span>/* ie8 */</span>
<span><span>filter</span>:<span><span>alpha(opacity=<span>50</span>)</span>;</span></span> <span>/* ie5-7 */</span>
<span><span>opacity</span>:<span> <span>0.5</span>;</span></span> <span>/* css standard, currently it works in most modern browsers */</span>
<span>}</span></span>
<!DOCTYPE html>
<html>
<head>
<style>
img
{
opacity:0.4;
filter:alpha(opacity=40); /* For IE8 and earlier */
}
img:hover
{
opacity:1.0;
filter:alpha(opacity=100); /* For IE8 and earlier */
}
</style>
</head>
<body>
<h1>图像透明度</h1>
<img src="http://www.jb51.neti/tulip_peach_blossom_w_s.jpg" alt="Peach Blossom" />
<p><b>注释：</b>在 IE 中，必须添加 <!DOCTYPE>，这样才能将 :hover 选择器用于除了 <a> 之外的其它元素。</p>
</body>
</html>