<!DOCTYPE?html>
<html>
<head>
<meta?http-equiv="Content-Type"?content="text/html;?charset=utf-8">
<title>透明度</title>
<style?type="text/css">
*{margin:?0;padding:?0;}
#box1{width:?200px;height:?200px;background:?red;filter:?alpha(opacity:30);opacity:?0.3;}
</style>
<script?type="text/javascript">
window.onload=function(){
var?v=document.getElementById('div1');
v.onmouseover=function(){
star(100);
}
v.onmouseout=function(){
star(30);
}
}
var?timer=null;
var?alpha=30;
function?star(iTarget){
????????var?v=document.getElementById('div1');
????clearInterval(timer);
????timer=setInterval(function(){
???? var?speed=0;
???? if(alpha>iTarget){
???? speed=-10;
???? }else{
???? speed=10;
???? }
?????if(alpha==iTarget){
????? clearInterval(timer);
?????}else{
??????alpha=alpha+speed;
??????v.style.filter='alpha(opacity:'+alpha+')'
??????v.style.opacity=alpha/100;
?????}
????},30)
}
</script>
</head>
<body>
<div?id="box1"></div>
</body>
</html>
2016-08-03
你的id定義為box1,但是你上面在getElementById('div1')的時候都寫成了div1