js 页面左右两侧居中广告代码

<！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=utf-8" /> <title>无标题文档</title> <style> #left{ width:200px;height:450px; position:absolute; left:0px; background:red; border:1px #000 solid} #right{width:200px;height:450px; position:absolute; right:0px; background:blue; border:1px #000 solid} #x,#y{ width:10px; height:10px;position:absolute;right:0px; top:0px;} </style> <script> window.onload=window.onscroll=function（） { var oLeft = document.getElementById（"left"）; var oRight = document.getElementById（"right"）; var scrollY=document.documentElement.scrollTop||document.body.scrollTop; var clientH = document.documentElement.clientHeight; var oCloseX =document.getElementById（"x"） var oCloseY =document.getElementById（"y"） oLeft.style.top=（clientH-oLeft.offsetHeight）/2+scrollY+"px"; oRight.style.top=（clientH-oRight.offsetHeight）/2+scrollY+"px"; oCloseX.onclick=function（） { this.parentNode.parentNode.removeChild（this.parentNode）; } } </script> </head> <body style="height:2000px;">x x</body> </html>

[Ctrl+A 全选注:如需引入外部Js需刷新才能执行]