解决ie6里png图片透明变白色bug

加入这段js就行了。

 function correctPNG() // correctly handle PNG transparency in Win IE 5.5 & 6.
 {
     var arVersion = navigator.appVersion.split("MSIE")
     var version = parseFloat(arVersion[1])
     if ((version >= 5.5) && (document.body.filters))
     {
         for(var j=0; j<document.images.length; j++)
         {
             var img = document.images[j]
             var imgName = img.src.toUpperCase()
             if (imgName.substring(imgName.length-3, imgName.length) == "PNG")
             {
                 var imgID = (img.id) ? "id='" + img.id + "' " : ""
                 var imgClass = (img.className) ? "class='" + img.className + "' " : ""
                 var imgTitle = (img.title) ? "title='" + img.title + "' " : "title='" + img.alt + "' "
                 var imgStyle = "display:inline-block;" + img.style.cssText
                 if (img.align == "left")
                     imgStyle = "float:left;" + imgStyle
                 if (img.align == "right")
                     imgStyle = "float:right;" + imgStyle
                 if (img.parentElement.href)
                     imgStyle = "cursor:hand;" + imgStyle
                 var strNewHTML = "<span " + imgID + imgClass + imgTitle
                     + " style=\"" + "width:" + img.width + "px; height:" + img.height + "px;" + imgStyle + ";"
                     + "filter:progid:DXImageTransform.Microsoft.AlphaImageLoader"
                     + "(src=\'" + img.src + "\', sizingMethod='scale');\"></span>"
                 img.outerHTML = strNewHTML
                 j = j-1
             }
         }
     }
 }
 window.attachEvent("onload", correctPNG);