解决ie6 png格式图片背景透明问题

function correctPNG()
{
	for(var i=0; i<document.images.length; i++)       
    {       
		var img = document.images[i]       
		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 + "\');\"></span>" 
            img.outerHTML = strNewHTML
            i = i-1       
		}
	}       
}