基于JS实现二维码图片固定在右下角并跟随滚动条滚动

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> 
<title>二维码图片固定在右下角某处并跟随滚动条滚动</title> 
</head> 
<body> 
<div style="width:1000px; height:1000px;">二维码图片固定在右下角某处并跟随滚动条滚动</div> 
<script language="javascript"> 
function wx_scroll(){  
 var topH=-80; 
 var leftW=10; 
 var sHeight,sWidth,cHeight; 
 //alert(document.documentElement.clientWidth); 
 (document.body.scrollLeft==0)?sWidth=document.documentElement.scrollLeft + document.documentElement.clientWidth - 260 :sWidth=document.body.scrollLeft+ document.documentElement.clientWidth - 260 ; 
 (document.body.scrollTop==0)?sHeight=document.documentElement.scrollTop+ document.documentElement.clientHeight - 260 :sHeight=document.body.scrollTop+ document.documentElement.clientHeight - 260; 
 document.getElementById("bar_float").style.left=eval(sWidth+leftW) +"px"; 
 document.getElementById("bar_float").style.top=eval(sHeight+topH) +"px"; 
} 
setInterval("wx_scroll()",100); 
</script> 
<div id="bar_float" style="position: absolute; display:block; z-index: 10000; left: 1216px; top: -80px;"> 
<div id="stayTopleft"> 
 <table cellspacing="0" cellpadding="0" border="0"> 
 <tbody> 
 <tr> 
  <td colspan="2" valign="top"><img src="weixin.jpg" width="253" height="253" border="0"></td> 
  </tr> 
  <tr> 
 </table></div> 
</div> 
</body> 
</html>