求大神指点
<!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>多物体分别运动宽、高 </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:4px solid #000; filter:alpha(opacity:30); opacity:0.3;}
</style>
<script>
window.onload = function(){
//var aLi = document.getElementsByTagName('li');
/*for(var i=0;i<aLi.length;i++){
aLi[i].timer = null;
aLi[i].onmouseover = function(){
startMove(this,400);
}
aLi[i].onmouseout = function(){
startMove(this,200);
}
}*/
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.currenStyle){
return obj.currentStyle[attr];
}else{
return getComputedStyle(obj,false)[attr];
}
}
//var timer = null;
var alpha = 30;
function startMove(obj,attr,iTarget){
clearInterval(obj.timer);
obj.timer = setInterval(function(){
var icur = 0;
if(icur=='opacity'){
icur = Math.round(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[attr] = icur+speed+'px';
}
}
},30);
}
</script>
</head>
<body>
<ul>
<li id='li1'></li>
</ul>
</body>
</html>
