网上的一段JS动态缩小图片的代码，缩略图好帮手，支持FF,IE,Chrome
<script language="JavaScript">
var flag=false;
function DrawImage(ImgD,imageWidth,imageHeight) {
var image=new Image();
image.src=ImgD.src;
if(image.width>0 && image.height>0){
flag=true;
if(image.width/image.height>= imageWidth/imageHeight){
if(image.width>imageWidth){
ImgD.width=imageWidth;
ImgD.height=(image.height*imageWidth)/image.width;
}else{
ImgD.width=image.width;
ImgD.height=image.height;
}
}
else{
if(image.height>imageHeight){
ImgD.height=imageHeight;
ImgD.width=(image.width*imageHeight)/image.height;
}else{
ImgD.width=image.width;
ImgD.height=image.height;
}
}
}
}
</script>

用法：<img src="xxx" onload="javascript:DrawImage(this,120,60) ;"/>