js计算机样式window.getComputedStyle(ele,null)2

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>window.getComputedStyle(div,null)</title>
    <style type="text/css">
        *{margin:0;padding:0}
    </style>
</head>
<body>
<div style=" 100px; height: 100px; background: red; position: absolute;left: 0; top:0"></div>
<script type="text/javascript">
    //封装
    function getStyle(elem,prop){
        if(window.getComputedStyle){        //如果它存在的话(兼容谷歌)
            return window.getComputedStyle(elem,null)[prop];//prop作为参数字符串传进来，所有得中括号
        }else{
            return elem.currentStyle[prop];   //兼容IE
        }
    }
    var timer;
    var div = document.getElementsByTagName('div')[0]
    timer=setInterval(function(){
        div.style.left=parseInt(getStyle(div,'left'))+1+"px";//注意：getStyle(div,'left')打印出来是0px,所以用parseInt取整数
    },10)
    div.onclick = function() {
        clearInterval(timer)
    }
</script>
</body>
</html>
效果图：