解决IE6下PNG图片不透明

PNG图片以插入方式使用

方法一：
制作一张透明小图片nothing.gif
添加样式
.pngfix {
azimuth: expression(
this.pngSet?this.pngSet=true:(this.nodeName == "IMG" && this.src.toLowerCase().indexOf('.png')>-1?(this.runtimeStyle.backgroundImage = "none",
this.runtimeStyle.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + this.src + "', sizingMethod='image')",
this.src = "transparent.gif"):(this.origBg = this.origBg? this.origBg :this.currentStyle.backgroundImage.toString().replace('url("','').replace('")',''),
this.runtimeStyle.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + this.origBg + "', sizingMethod='crop')",
this.runtimeStyle.backgroundImage = "none")),this.pngSet=true);
}
对需要处理的PNG图片运用上面样式

方法二：
调用js代码对全站png图片处理
<!--[if IE 6]>
<script>
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 + "', sizingMethod='scale');\"></span>";
img.outerHTML = strNewHTML;
i = i-1;
}
}
}
window.attachEvent("onload", correctPNG);
</script>
<![endif]--> ​

PNG图片作为背景图使用

方法一
用IE专用HACK调用gif图片
.pngImg { background:url(image.png); _background:url(image.gif);}

方法二
PNG图片容器添加下面样式
background:url(your.png);
_background: none;
_filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src='your.png',sizingMethod="crop");
注意：样式定义顺序有要求
缺点：背景图不能平铺，容器内非透明区域的链接按钮会失去焦点，可对链接或按钮添加样式position:relative;