DZ7.0自动伸缩广告

<div id="divbig" style="width:100%; height:300px;font-size:0px;"><img id="imgs" style="width:100%"></div>
   <script language="javascript">
     var ishow=10;
     var jshow=5,d;

    var  bigimg="http://www.myzyb.cn/images/adpic/big.gif";
    var smallimg="http://www.myzyb.cn/images/adpic/small.gif";
    var bigurl="http://www.myzyb.cn/forum-91-1.html";
    var smallurl="http://www.myzyb.cn/forum-76-1.html";

     d=document.getElementById("divbig");
m=document.getElementById("imgs");       event1();
       function show1()
     {
       event1();
  if(d.style.height=="9px"||d.style.height=="10px")
         {
           d.style.height=0;
          event2();
           setTimeout("show2()",20);
           return;
         }
         m.style.height=300-ishow+"px";
         d.style.height=300-ishow+"px";
         ishow=ishow+10;
         setTimeout("show1()", 2);
    }

     function show2()
     {
           event2();
 if(d.style.height=="100px")
        {
            return;
        }
        m.style.height=jshow+"px";
        d.style.height=jshow+"px";
        jshow+=5;
        setTimeout("show2()", 1);
     }
     window.onload=function()
     {
          setTimeout("show1()",5000);
     }

     function event1()
     {
         m.src=bigimg;
         d.style.cursor="pointer";
         d.onclick=function()
         {
            window.open(bigurl);
         }
     }

     function event2()
     {
         m.src=smallimg;
         d.style.cursor="pointer";
         d.onclick=function()
         {
            window.open(smallurl);
         }
     }
</script>