function ElementUpDown(obj,classobj)
{ 			
	if (document.documentElement && document.documentElement.scrollTop)
	{
		classobj.diffY = document.documentElement.scrollTop;			
	}	
	else if (document.body)
	{
		classobj.diffY = document.body.scrollTop;			
	}	
			
	classobj.percent=.1*(classobj.diffY-classobj.lastScrollY); 
	if(classobj.percent>0)
	{
		classobj.percent=Math.ceil(classobj.percent); 
	}
	else
	{
		classobj.percent=Math.floor(classobj.percent); 
	}
	if(document.getElementById(obj) != null)
	{			
		document.getElementById(obj).style.top=parseInt(document.getElementById(obj).style.top)+classobj.percent+"px";		
	}
	classobj.lastScrollY=classobj.lastScrollY+classobj.percent;		
}
// 定义一个类  用来保存位置
var class_obj = function()
{
	this.lastScrollY = function(){return this.lastScrollY;};
	this.diffY = function(){return this.diffY;};
	this.percent = function(){return this.percent;};
}
/*
//显示代码 注意每个标签的ID 必须唯一
function showHTMl()
{
	document.write("<div id=\"freetelphone\" style=\"position:absolute;right:100px;top:100px;\">"+
	"<img src=\"http://img1.qq.com/sports/pics/18068/18068381.jpg\"/>"+
	"</div>");
	
	document.write("<div id=\"freetelphone2\" style=\"position:absolute;right:200px;top:200px;\">"+
	"<img src=\"http://img1.qq.com/sports/pics/18068/18068381.jpg\"/>"+
	"</div>");
					
}						
showHTMl();		
var a = new class_obj();
a.lastScrollY = 0;
a.diffY = 0;
a.percent = 0;	
var b = new class_obj();
b.lastScrollY = 0;
b.diffY = 0;
b.percent = 0;		

setInterval("ElementUpDown('freetelphone',a)",1);
setInterval("ElementUpDown('freetelphone2',b)",1);
*/