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纯CSS实现的图片圆角边框效果,兼容IE6.
实现原理很简单,利用绝对定位,使一个背景为PNG图片的边框覆盖在原始图片上面.而兼容IE6,本文用的是一段JS来让万恶的万万人诅咒的IE6识别PNG图片的.当然,你还可以用滤镜的方式让IE6实现PNG效果.本文后面我会附上两种解决方案.个人比较推崇用JS来实现IE6PNG,适应性比较强,但如果你只有一两处用到PNG,完全可以用滤镜的方式来实现.
核心CSS代码:

.i_roundimg{ background:url(http://mrthink.net/demo/images/100508.png) no-repeat;cursor:pointer;width:60px;height:60px;position:absolute;}

DEMO用到的PNG背景图片:
另外附上两种解决IE6下PNG图片的方案:
JavaScript让IE6识别PNG(适应性强,适应于背景PNG和页面中的PNG):

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EvPNG.fix("div,span");  //EvPNG.fix("@Mr.Think提示你:请在此处设置包含透明PNG图片的标签"),多个标签之间用英文逗号隔开.

IE滤镜让IE6实现PNG效果(适应性差,一般用于仅一两处用到PNG背景的情况):

filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(src="http://mrthink.net/demo/images/100508.png",sizingMethod="scale");

本文来源：http://www.gbppp.com/lzmw/566230/