js效果 图片加载进度实时显示

<script>
var l=0;
var imgs;
var sum=0;
var imgs=new Array();
function chk(){
  l--;
  document.getElementById("aa").innerText=""+((sum-l)*100/sum)+"%"
  if (l==0){
     for (var i=0;i<sum;i++)
       document.body.innerHTML+="<img src='"+imgs[i].src+"'>"
  }
}
if (document.images){
imgs[0]=new Image()
imgs[1]=new Image()
imgs[2]=new Image()
imgs[3]=new Image()
imgs[4]=new Image()
imgs[5]=new Image()
imgs[6]=new Image()
imgs[7]=new Image()
imgs[0].src="/articleimg/2006/08/3859/01.jpg";
imgs[1].src="/articleimg/2006/08/3859/02.jpg";
imgs[2].src="/articleimg/2006/08/3859/03.jpg";
imgs[3].src="/articleimg/2006/08/3859/04.jpg";
imgs[4].src="/articleimg/2006/08/3859/05.jpg";
imgs[5].src="/articleimg/2006/08/3859/06.jpg";
imgs[6].src="/articleimg/2006/08/3859/07.jpg";
imgs[7].src="/articleimg/2006/08/3859/08.jpg";
}
</script>
<body>
<div id="aa">0%</div>
<script>
sum=l=imgs.length;
for (var i=0;i<l;i++){
  imgs[i].onload=chk;
  imgs[i].onerror=chk;//无论图片是否加载成功，都执行指定方法
}
</script>
</body>