Code to make IE support RGBa background color_javascript skills

Above code:

<title>Demo</title> <style type="text/css"> #div1 { padding: 10px; width: 380px; height: 205px; background: url(/upload/201007/20100713220102894.jpg); } #div2 { color: #FFF; font-size: 40px; font-weight: bold; text-align: center; height: 205px; line-height: 205px; background: rgba(125, 0, 0, .3); filter: progid:DXImageTransform.Microsoft.gradient(startColorstr=#4B7D0000 ,endColorstr=#4B7D0000); } </style> <div id="div1"> <div id="div2"> Hello world! </div> </div>
[Ctrl A Select all Note: If you need to introduce external Js, you need to refresh to execute ]

DXImageTransform.Microsoft.gradient filter The startColorstr parameter value in the mirror is in the form of #AARRGGBB, where AA is hexadecimal representing opacity, 00 means completely transparent, FF means fully opaque, the decimal range is 0~255, and the remaining RRGGBB is the color hexadecimal code. In the example, background: rgba(125, 0, 0, .3); represents a red background with 30% opacity. How to convert 30% opacity to hexadecimal? It's very simple. First calculate the decimal x of #AA, x/255 = 3/10, and the solution is x=3*255/10, and then convert x to hexadecimal, which is approximately equal to 4B.

Attached below are the pictures used in the examples:

Author: Zhou Mingzhi
Part of the article comes from: RGBa Browser Support