js获取css样式封装

封装
	  function getStyle(obj , attr){
		return obj.currentStyle?obj.currentStyle[attr]:getComputedStyle(obj)[attr]; //兼容写法IE:火狐
	  };

效果如下：

<!doctype html>
<html lang="en">
 <head>
  <meta charset="UTF-8">
  <meta name="Generator" content="EditPlus®">
  <meta name="Author" content="">
  <meta name="Keywords" content="">
  <meta name="Description" content="">
  <title>Document</title>
  <style>
	*{
		margin: 0;
		padding: 0;
	}
	#box{
		margin: 50px auto;
		 300px;
		height: 250px;
		color: #fff;
		background:#70aa39;
		text-align: center;
		line-height: 50px;
	}
  </style>
 </head>
 <body>
	<div id="box"></div>
 <script>
	var oBox = document.getElementById("box"),
		oW = parseFloat(getStyle(oBox , "width")),
		oH = parseFloat(getStyle(oBox , "height"));
		oBox.innerHTML = "宽:"+oW+"px"+"<br/>"+"高:"+oH+"px";
	//封装
	  function getStyle(obj , attr){
		return obj.currentStyle?obj.currentStyle[attr]:getComputedStyle(obj)[attr]; //兼容写法IE:火狐
	  };
  </script>
 </body>
</html>