ie6 下fixed 定位 js

绝对定位
下面是蓝色上高手用js写的：http://bbs.blueidea.com/thread-2979799-1-1.html
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gbk" />
<title>Untitled Document</title>
<style>
	html,body{
		padding:0;
		margin:0;
	}
</style>
</head>
<body>
	<div id="aa" style="100px;height:100px;background:#c0c0c0;" >我在随平滚</div>
	<div id="bb" style="100px;height:100px;background:#c0c0c0;" >我静止不动</div>
	<div style="100%;height:1500px;background:#000"></div>
	<div style="100%;height:1500px;background:green"></div>
	<div style="100%;height:1500px;background:red"></div>
</body>
</html>
<script>
   	function scroll(p){
    	var d = document,dd = d.documentElement,db = d.body,w = window,o = d.getElementById(p.id),ie = /msie/i.test(navigator.userAgent),style,timer;
    	if(o){
			//ie8下position:fixed下top left失效
    		o.style.cssText +=";position:"+(p.f&&!ie?'fixed':'absolute')+";"+(p.l==undefined?'right:0;':'left:'+p.l+'px;')+(p.t!=undefined?'top:'+p.t+'px':'bottom:0');
    		if(p.f&&ie){
				o.style.cssText +=';left:expression(body.scrollLeft + '+(p.l==undefined?db.clientWidth-o.offsetWidth:p.l)+' + "px");top:expression(body.scrollTop +'+(p.t==undefined?db.clientHeight-o.offsetHeight:p.t)+'+ "px" );'
				db.style.cssText +=";background-image:url(about:blank);background-attachment:fixed;"
			}else{
				if(!p.f){
					 w.onresize = w.onscroll = function(){
						clearInterval(timer);
						timer = setInterval(function(){
							var st = db.scrollTop,c;
							c = st  - o.offsetTop + (p.t!=undefined?p.t:(w.innerHeight||db.clientHeight)-o.offsetHeight);
							if(c!=0){
								o.style.top = o.offsetTop + Math.ceil(Math.abs(c)/10)*(c<0?-1:1) + 'px';
							}else{
								clearInterval(timer);		
							}
						},10)
					}
				}
			}
    	}  
    }
    scroll({
    	id:'aa'
	
    })
	 scroll({
		id:'bb',
		l:0,
		t:200,
		f:1
	 })
    /*
    	id 你要滚动的内容的id
    	l 横坐标的位置  不写为紧贴右边
    	t 你要放在页面的那个位置默认是贴着底边 0是贴着顶边
    	f 1表示固定 不写或者0表示滚动
    */
</script>