js浮动窗口居中显示！求高手帮忙看下代码哪里错了！
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
<style>
body { margin: 0; height: 2000px; }
p{margin:0;}
#mask { position: absolute; left: 0; top: 0; width: 100%; height: 100%; background: #000; opacity: 0.3; filter:alpha(opacity:30); display:none; }
#box { width: 300px; height: 300px; position: fixed; _position: absolute; left: 0; top: 0; background: #fff; border: 5px solid #333; display:none;}
#box p{height:40px;line-height:40px;background:#ccc;}
#box p a{float:right;width:32px;height:32px;background:url(img/close.png);margin:4px 0;}
#login{position:fixed;_position:absolute;padding:0 20px;font-size:16px;text-decoration:none;border:solid 1px #ccc;background:#03F;color:#fff;height:30px;line-height:30px;}
#login:hover{background:#09F;color:red;}
</style>
<script src="js/DD_belatedPNG_0.0.8a.js" type="text/javascript"></script>
<!--[if IE 6]>
<script src="js/DD_belatedPNG_0.0.8a.js" type="text/javascript"></script>
<script type="text/javascript">
DD_belatedPNG.fix('#box a');
</script>
<![endif]-->
</head>
<body>
<a href="javascript:;" id="login">登录</a>
<div id="mask"></div>
<div id="box">
<p><a href="javascript:;"></a></p>
</div>
</body>
</html>
<script>
var oMask = document.getElementById('mask');
var oBox = document.getElementById('box');
var oClose=oBox.getElementsByTagName('a')[0];
var oLogin=document.getElementById('login');
var iH = Math.max(view().h,offsetH(),scrollH());
oMask.style.height = iH + 'px';
window.onload = function(){
fnAdjust();
oLogin.onclick=function()
{
show();
fnAdjust();
}
oClose.onclick=function()
{
hide();
}
};
function fnAdjust()
{
var iLeft = ( view().w - oBox.offsetWidth ) / 2;
var iTop = ( view().h - oBox.offsetHeight ) / 2;
var iLoginTop=20;
if( isIe6() )
{
iTop += scrollY();
iLoginTop+=scrollY();
}
oBox.style.left = iLeft + 'px';
oBox.style.top = iTop + 'px';
oLogin.style.right = '20px';
oLogin.style.top = iLoginTop + 'px';
}
function show()
{
oBox.style.display='block';
oMask.style.display='block';
}
function hide()
{
oBox.style.display='none';
oMask.style.display='none';
}
window.onresize = window.onscroll=function()
{
fnAdjust();
}
/*
clientHeight:
offsetHeight:
scrollHeight:
*/
function scrollY(){
return document.body.scrollTop
[解决办法]
document.documentElement.scrollTop;
}
function view(){
return {
w : document.documentElement.clientWidth,
h : document.documentElement.clientHeight
};
}
function offsetH(){
return document.body.offsetHeight;
}
function scrollH(){
return document.body.scrollHeight;
}
function isIe6(){
var str = window.navigator.userAgent.toLowerCase();
if( str.indexOf('msie 6') != -1)return true;
return false;
}
</script>
