div always centered JS code _javascript tips

Copy Code code as follows:

<! DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 transitional//en" "Http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd ">
<meta http-equiv= "Content-type" content= "text/html; Charset=utf-8 "/>
<title> Side Bar Advertising </title>
<style type= "Text/css" >
#show {width:100px; height:80px; background: #0f0; position:fixed; _position:absolute; right:0px; top:0px;}
</style>
<script type= "Text/javascript" >
Window.onscroll = Window.onresize = Window.onload = function () {

var odiv = document.getElementById ("show");
var sTop = Document.documentElement.scrollTop | | Document.body.scrollTop;
var cheight= document.documentElement.clientHeight | | Document.body.clientHeight;
var mid = (cheight-odiv.offsetheight)/2;
ODiv.style.top = parseint (STop + mid) + "px"; Theoretically, this is the only sentence that can be centered.

In fact, the major browsers only know the following if judgment
if (Navigator.appVersion.indexOf ("MSIE 6") >-1) {
ODiv.style.top = parseint (STop + mid) + "px";
}else{
ODiv.style.top =mid + "px";
}
}