为什么这个函数后面运行的那个函数先运行了
应该宽变宽之后跳出a，可是一开始就跳出a了
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>任意属性值2</title>
<style type="text/css">
body,div{ padding:0;margin:0;font:normal 12px "微软雅黑"}
div{
width:200px;
height:150px;
background-color: gold;
top:20px;
left:20px;
filter: alpha(opacity:30);
opacity: 0.3;
float:left;
margin-left:20px
}
</style>
<script type="text/javascript">
window.onload=function() {
var box = document.getElementById("box");
box.alpha=30;
box.timer=null;
box.onmouseover = function(){startMove(this,'width',300,alert("a"))};
};
function startMove(obj,attr,target,fn){
clearInterval(obj.timer);
obj.timer=setInterval(
function(){
var icur=0;
if(attr=='opacity'){
icur=Math.round(parseFloat(getStyle(obj,attr))*100)
}else{
icur= parseInt(getStyle(obj,attr));
}
var speed=(target-icur)/8;
speed=speed>0?Math.ceil(speed):Math.floor(speed);
if(icur==target){
clearInterval(obj.timer);
if(fn){
fn()
}
}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)
}
function getStyle(obj,attr){
if(obj.currentStyle){
return obj.currentStyle[attr];
}else{
return getComputedStyle(obj,false)[attr];
}
}
</script>
</head>
<body>
<div id="box"></div>
</body>
</html>
