图片放大的js

/**
*<img src="" zoomImg="1"/>
*<script language="javascript" type="text/javascript" src="/js/zoomImg.js"></script>
*/
(function zoomImg(){
	var d = document,e = d.getElementsByTagName("IMG");
	if(e){
		for(var i=0; i<e.length; i++){
			try{
				var is = e[i] && e[i].getAttribute && e[i].getAttribute("zoomImg") && e[i].getAttribute("zoomImg") == "1";
				if(is){
					var oImage = new Image();
						oImage.onload = function(){
							var w = this.width;
							var h = this.height;
							var oImg = this.linkObj;
							var _w = oImg.width;
							var _h = oImg.height;
							
							if(_w && _h){
								if(parseInt(w)>_w || parseInt(h)>_h){
									var r = _h/parseInt(h);
									if( r > (_w/parseInt(w)) ){
										r = _w/parseInt(w);
									}
									oImg.style.width = (parseInt(w)*r)+"px";
									oImg.style.height = (parseInt(h)*r)+"px";
								}else{
									oImg.style.width = w+"px";
									oImg.style.height = h+"px";
								}
							}
						}
						oImage.linkObj = e[i];
						oImage.src = e[i].src;
						
				}
			}
			catch(b){}
		}
	}
})();