随滚动条滚动的居中div

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transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"> 遨游、火狐浏览器就用这个吧-->
<!DOCTYPE>
<<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>无标题</title>
</head>
<body>

</body>
</html>
<head>
    <meta charset="UTF-8">
    <title>随滚动条滚动的居中div</title>
   
    <script type="text/javascript">
    function scrollBox(){
                document.getElementById("centerBox").style.top=(document.documentElement.scrollTop+
        (document.documentElement.clientHeight-document.getElementById("centerBox").offsetHeight)/2)+"px";
                document.getElementById("centerBox").style.left=(document.documentElement.scrollLeft+
        (document.documentElement.clientWidth-document.getElementById("centerBox").offsetWidth)/2)+"px";
    }
    window.onload=function(){
        scrollBox();
    }
    window.onscroll=function(){
        scrollBox();
    }

// function test(){
    //     scrollBox();
    // }
    // window.onscroll=test;//注意别写成onScroll,JS是区分大小写的，我就因为写错了，搞了半天效果都没出来
    // window.onload=test;//注意别写成onLoad
    </script>
</head>
<body>
<div style="width:400px; height:400px; border:1px solid #f1f1f1; background-color:red; position:absolute;
top:0px; left:0px;" id="centerBox"></div>
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</body>
</html>

PS：QMM亲自动手做的，自己做的总有成就感！