<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>获取属性动画2</title>
<style type="text/css">
*{margin:0; padding:0;}
ul,li{
list-style: none;
}
ul li{
width: 200px;
height: 100px;
background: yellow;
margin-bottom: 20px;
border: 10px solid #000;
filter:alpha(opacity:30);
opacity:0.3;
}
</style>
<script type="text/javascript">
window.onload=function(){
var Li1=document.getElementById('li1');
Li1.onmouseover=function(){
startMove(this,'opacity',100);
}
Li1.onmouseout=function(){
startMove(this,'opacity',30);
}
}
function getStyle(obj,attr){
if(obj.currentStyle){
return obj.currentStyle[attr];}//针对IE浏览器
else{
return getComputedStyle(obj,false)[attr];//针对火狐浏览器
}
}
//var timer=null;
var alpha=30;
function startMove(obj,attr,iTarget)
{
clearInterval(obj.timer);
obj.timer=setInterval(function()
{
var icur=0;
if(attr=='opacity')
{
icur=parseFloat(getStyle(obj.attr))*100;
}
else
{
icur=parseInt(getStyle(obj,attr));
}
var speed=(iTarget-icur)/8;
speed=speed>0?Math.ceil(speed):Math.floor(speed);
if(icur==iTarget)
{
clearInterval(obj.timer);
}
else
{
if(attr=='opacity'){
obj.style.filter='alpha(opacity:'+(icur+speed)+')';
obj.style.opacity=(icur+speed)/100;
}
else{
//obj.style.width=icur+speed+'px';
obj.style[attr]=icur+speed+'px';
}
}
},30)
}
</script>
</head>
<body>
<ul>
<li id="li1"></li>
</ul>
</body>
</html>第51行
parseFloat(getStyle(obj.attr))
你写错了，中间是","。
应该是
parseFloat(getStyle(obj,attr))
这样就没问题了