JS中for循序中延迟加载动态效果的具体实现

<script src="js/jquery-1.7.1.min.js" type="text/javascript"></script>
<script type="text/javascript">
  $(function(){ 

    for(var i=1; i<6;i++)
    {
      var a=$("#zhong"+i+"").height();   //获取高度
      $("#zhong"+i+"").attr("OldHeight",a); //设置OldHeight属性
    }
    var e=0; //定义一个值
    interid=setInterval(Showgao,30);  //setInerval 每隔30ms加载一次
    function Showgao()
    {
       e++;
       for(var x=1;x<6;x++)
       {
         var b= $("#zhong"+x+"").attr("OldHeight");    

         if(typeof(b) == "undefined"||b!="")
         {
           if(e>b){$("#zhong"+x+"").height(b);}
           else{$("#zhong"+x+"").height(e);}
         }
       }
       if(e==1000){clearInterval(interid);}
    }

  });
</script>

<div class="zhu no1">
       <div class="tou"><img src="images/toubg.png" /></div>
       <div id="zhong1" class="zhong" style="height:66px;"></div>
       <div class="wei"><img src="images/weibg.png" /></div>
     </div>
      <div class="zhu no2">
       <div class="tou"><img src="images/toubg.png" /></div>
       <div id="zhong2" class="zhong" style="height:0px;"></div>
       <div class="wei"><img src="images/weibg.png" /></div>
     </div>
     <div class="zhu no3">
       <div class="tou"><img src="images/toubg.png" /></div>
       <div id="zhong3" class="zhong" style="height:22px;"></div>
       <div class="wei"><img src="images/weibg.png" /></div>
     </div>     
     <div class="zhu no4">
       <img src="images/huisebg.png" />
     </div>