function ImgShow(evt){
			var imgTag=(window.event)?event.srcElement:evt.target;
			var imgPath=imgTag.src.replace("a.jpg",".jpg");//取得弹出的大图url
			var tagTop=Math.max(window.top.document.documentElement.scrollTop,window.top.document.body.scrollTop);
			var tag=window.top.document.createElement("div");
				tag.style.cssText="width:100%;height:"+Math.max(window.top.document.body.clientHeight,window.top.document.body.offsetHeight)+"px;position:absolute;background:white;top:0;filter: Alpha(Opacity=80);Opacity:0.8;";
				tag.ondblclick=function(){var clsOK=confirm("确定要取消图片显示吗?"); if(clsOK){closes();}};
			var tagImg=window.top.document.createElement("div");
			    tagImg.setAttribute("id","showpic");
				tagImg.style.cssText="font:12px /18px verdana;overflow:auto;text-align:center;position:absolute;width:200px;border:5px solid gray;background:gray;color:white;left:"+(parseInt(window.top.document.body.offsetWidth)/2-100)+"px;top:"+(window.top.document.documentElement.clientHeight/3+tagTop)+"px;"
				tagImg.innerHTML="<div style='padding:10px;background:#cccccc;border:1px solid white'><img src='images/wait2.gif'/><br /><br /><b style='color:#999999;font-weight:normal'>Image loading...</b><br /></div>";
			    
			var closeTag=window.top.document.createElement("div");
				closeTag.style.cssText="display:none;position:absolute;left:10px;top:10px;background:red;border:1px solid white;yellow:white;filter:Alpha(Opacity=50);Opacity:0.5;cursor:pointer;";
				closeTag.innerHTML="<b> 关闭 </b>";
				closeTag.onclick=closes;
			window.top.document.body.appendChild(tag);
			window.top.document.body.appendChild(tagImg);
			//var img=new Image();
			var img=window.top.document.createElement("img");
				img.src=imgPath;
				img.style.cssText="border:1px solid #cccccc;filter: Alpha(Opacity=0);Opacity:0;";
				tagImg.oncontextmenu=function(){var clsOK=confirm("确定要取消图片显示吗?"); if(clsOK){closes();};return false};
			    
			var barShow,imgTime;
			img.complete?ImgOK():img.onload=ImgOK;
			function ImgOK(){
				var Stop1=false,Stop2=false,temp=0;
				var tx=tagImg.offsetWidth,ty=tagImg.offsetHeight;
				var ix=img.width,iy=img.height;
				var sx=window.top.document.documentElement.clientWidth,sy=Math.min(window.top.document.documentElement.clientHeight,window.top.document.body.clientHeight/*opera*/);
				var xx=ix>sx?sx-50:ix+4,yy=iy>sy?sy-50:iy+3;
				var maxTime=setInterval(function(){
					temp+=35;
					if((tx+temp)<xx){
						tagImg.style.width=(tx+temp)+"px";
						tagImg.style.left=(sx-(tx+temp))/2+"px";
					}else{
						Stop1=true;
						tagImg.style.width=xx+"px";
						tagImg.style.left=(sx-xx)/2+"px";
					}
					if((ty+temp)<yy){
						tagImg.style.height=(ty+temp)+"px";
						tagImg.style.top=(tagTop+((sy-(ty+temp))/2))+"px";
					}else{
						Stop2=true;
						tagImg.style.height=yy+"px";
						tagImg.style.top=(tagTop+((sy-yy)/2))+"px";
					}
					if(Stop1&&Stop2){
						clearInterval(maxTime);
						tagImg.appendChild(img);
						temp=0;
						imgOPacity();
					}
				},1);
				function imgOPacity(){
					temp+=10;
					img.style.filter="alpha(opacity="+temp+")";
					img.style.opacity=temp/100;
					imgTime=setTimeout(imgOPacity,1)
					if(temp>100) clearTimeout(imgTime);
				}
				tagImg.innerHTML="";
				tagImg.appendChild(closeTag);
				if(ix>xx||iy>yy){
					img.alt="左键拖动,双击放大缩小";
					img.ondblclick=function (){
						if(tagImg.offsetWidth<img.offsetWidth||tagImg.offsetHeight<img.offsetHeight){
							img.style.width="auto";
							img.style.height="100%";
							img.alt="双击可以放大";
							img.onmousedown=null;
							closeTag.style.top="10px";
							closeTag.style.left="10px";
							tagImg.style.overflow="visible";
							tagImg.style.width=img.offsetWidth+"px";
							tagImg.style.left=((sx-img.offsetWidth)/2)+"px";
						}else{
							img.style.width=ix+"px";
							img.style.height=iy+"px";
							img.alt="双击可以缩小";
							img.onmousedown=dragDown;
							tagImg.style.overflow="auto";
							tagImg.style.width=xx+"px";
							tagImg.style.left=((sx-xx)/2)+"px";
						}
					}
					img.onmousedown=dragDown;
					tagImg.onmousemove=barHidden;
					tagImg.onmouseout=moveStop;
					window.top.document.onmouseup=moveStop;
				}else{
					tagImg.style.overflow="visible";
					tagImg.onmousemove=barHidden;
				}
			}
			function dragDown(a){
				img.style.cursor="pointer";
				var evts=a||window.event;
				var onx=evts.clientX,ony=evts.clientY;
				var sox=tagImg.scrollLeft,soy=tagImg.scrollTop;
				var sow=img.width+2-tagImg.clientWidth,soh=img.height+2-tagImg.clientHeight;
				var xxleft,yytop;
				window.top.document.onmousemove=function(e){
					var evt=e||window.event;
					xxleft=sox-(evt.clientX-onx)<0?"0":sox-(evt.clientX-onx)>sow?sow:sox-(evt.clientX-onx);
					yytop=soy-(evt.clientY-ony)<0?"0":soy-(evt.clientY-ony)>soh?soh:soy-(evt.clientY-ony);
					tagImg.scrollTop=yytop;
					tagImg.scrollLeft=xxleft;
					closeTag.style.top=(yytop+10)+"px";
					closeTag.style.left=(xxleft+10)+"px";
					return false;
				}
				return false;
			}
			function barHidden(){
				clearTimeout(barShow);
				if(closeTag.style.display=="none")closeTag.style.display="block";
				barShow=setTimeout(function(){closeTag.style.display="none";},2000);
			}
			function closes(){
				window.top.document.body.removeChild(tag);
				window.top.document.body.removeChild(tagImg);
				clearTimeout(barShow);
				clearTimeout(imgTime);
				window.top.document.onmouseup=null;
				tag=img=tagImg=closeTag=null;
			}
			function moveStop(){
				window.top.document.onmousemove=null;
				tagImg.onmousemove=barHidden;
				img.style.cursor="default";
			}
		}