PNG格式在火狐下的背景是透明的，在IE下不是，下面一段JS能使PNG格式的图片背景透明
<script>
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
}
}
function test(){
alert('test');
window.onload=function(){ correctPNG();test(); }
</script>
介绍一下这个，window.onload=function(){ correctPNG();test(); }
有时候需要onload几个函数，就可以用上面的这种方法了。