为什么我跟着老师敲的代码，同时运动用json替代以后，没有效果？
function startMove(obj, json, fn) {
clearInterval(obj.timer); //清除定时器，避免重复生成多个定时器
obj.timer = setInterval(function() {
var flag = true; //假设刚开始时所有运动都已完成
for (var attr in json) { //遍历json
var icur = null;
//1.判断类型
if (attr == 'opacity') {
icur = Math.round(parseFloat(getStyle(obj, attr)) * 100);
} else {
icur = parseInt(getStyle(obj, attr));
}
//2.算速度
var speed = (json[attr] - icur) / 10;
speed = speed > 0 ? Math.ceil(speed) : Math.floor(speed);
//3.检测停止
if (icur != json[attr]) {
flag = false;
}
if (attr == 'opacity') {
obj.style.filter = 'alpha(opacity:' + (icur + speed) + ')';
obj.style.opacity = (icur + speed) / 100;
} else {
obj.style[attr] = icur + speed + 'px';
}
}
if (flag) { //当所有运动都完成时，清除定时器
clearInterval(obj.timer);
if (fn) {
fn();
}
}
}, 30);
}
function getStyle(obj, attr) {
if (obj.currentStyle) {
return obj.currentStyle[attr];
} else {
return getComputedStyle(obj, false)[attr];
}
}HTML文档——————————
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>同时运动</title>
<style>
*{
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;
}
<script src="js/move.js"></script>
<script>
window.onload=function(){
var oLi=document.getElementById('li1');
oLi.onmouseover=function(){
startMove1(oLi,{width:400,height:200});
}
}
</script>
</style>
</head>
<body>
<ul>
<li id="li1"></li>
</ul>
</body>
</html>
