求大神帮忙看看为什么没效果
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style>
*{margin:0; padding:0}
ul li{width:200px; height:100px; background:yellow; margin-bottom:10px; border:4px solid #000; filter:alpha(opacity=30); opacity:0.3}
</style>
<script>
window.onload=function(){
var li1=document.getElementById("li1")
li1.onmouseover=function(){
Move(this,"opacity",100);}
li1.onmouseout=function(){
Move(this,"opacity",30);}
}
function getStyle(obj,attr){
if(obj.currentStyle){
return obj.currentStyle[attr];
}
else{
return getComputedStyle(obj,false)[attr];
}
}
function Move(obj,attr,target){
clearInterval(obj.time)
obj.time=setInterval(function(){
var icur=0;
if(icur=="opacity"){
icur=Math.round(parseFloat(getStyle(obj,attr))*100)
}
else{
icur=parseInt(getStyle(obj,attr))
}
var speed=(target-icur)/8
speed=speed<0?Math.floor(speed):Math.ceil(speed)
if(icur==target){
clearInterval(obj.time)}
else{
if(icur=="opacity"){
obj.style.filter="alpha(opacity:"+(icur+speed)+")"
obj.style.opacity=(icur+speed)/100;
}
else{
obj.style[attr]=icur+speed+"px"}}
},30)
}
</script>
</head>
<body>
<ul>
<li id="li1"></li>
</ul>
</body>
</html>
