js实现兼容IE、Firefox的图片缩放代码

function SetSize(obj, width, height) {  myImage = new Image();  myImage.src = obj.src;  if (myImage.width > 0 && myImage.height > 0) {    var rate = 1;    if (myImage.width > width || myImage.height > height) {      if (width / myImage.width < height / myImage.height) {        rate = width / myImage.width;      } else {        rate = height / myImage.height;      }    }    if (window.navigator.appName == "Microsoft Internet Explorer") {      obj.style.zoom = rate;    } else {      obj.width = myImage.width * rate;      obj.height = myImage.height * rate;    }  }}