漂浮广告，关闭按钮

Code
<%@ Control Language="C#" AutoEventWireup="true" Inherits="controls_floatad" Codebehind="floatad.ascx.cs" %>
<script type="text/javascript">
function hidefudongand()
{
document.getElementById("fudongand").style.display="none";
}
</script>
<div id="fudongand" style="position:absolute;width:140px;"><!--一定要写宽度-->
<!--<div onclick="hidefudongand();" style="cursor:pointer;text-align:left;"></div>-->
<div><a href="http://www.hzxltz.com/topiccontent.aspx?id=140" target="_blank">
<img src="http://www.hzxltz.com/andimages/zhaopin.gif" alt="" border="0" />
</a></div><div style="float:right;"><span style="CURSOR:pointer;color:red;" onclick="hidefudongand();">关闭</span></div>

</div>
<script type="text/javascript">
var x = 50,y = 60;
var xin = true, yin = true;
var step = 1;//层移动的步长，值越大移动速度越快
var delay = 20;//层移动的时间间隔,单位为毫秒，值越小移动速度越快
var obj=document.getElementById("fudongand");
function floatAD()
{
var L=T=0;
var R= document.body.clientWidth-obj.offsetWidth;
var B = document.body.clientHeight-obj.offsetHeight;
obj.style.left = x + document.body.scrollLeft + "px";
obj.style.top = y + document.body.scrollTop +"px";
x = x + step*(xin?1:-1);
if (x < L) { xin = true; x = L;}
if (x > R){ xin = false; x = R;}
y = y + step*(yin?1:-1)
if (y < T) { yin = true; y = T; }
if (y > B) { yin = false; y = B;}
}
//如果需要显示漂浮广告，请注释掉下面这行代码，然后回复下面那三条已经注释掉的代码
//document.getElementById("fudongand").style.display="none";
var itl= setInterval("floatAD()", delay);
obj.onmouseover=function(){clearInterval(itl)}
obj.onmouseout=function(){itl=setInterval("floatAD()", delay)}
</script>