<html>

<head>

<title>JS實現(xiàn)5秒鐘自動封鎖div層</title>

<style type="text/css">

<!--

#sponsorAdDiv {position:absolute; height:1; width:1; top:0; left:0;}

-->

</style>

</head>

<body>

<SCRIPT LANGUAGE="JavaScript1.2">

adTime=5;  //封鎖窗口期待的時間

chanceAd=1;

var ns=(document.layers);

var ie=(document.all);

var w3=(document.getElementById && !ie);

adCount=0;

function initAd(){

        if(!ns && !ie && !w3) return;

        if(ie)                adDiv=eval('document.all.sponsorAdDiv.style');

        else if(ns)        adDiv=eval('document.layers["sponsorAdDiv"]');

        else if(w3)        adDiv=eval('document.getElementById("sponsorAdDiv").style');

        randAd=Math.ceil(Math.random()*chanceAd);

        if (ie||w3)

        adDiv.visibility="visible";

        else

        adDiv.visibility ="show";

        if(randAd==1) showAd();

}

function showAd(){

if(adCount<adTime*10){adCount+=1;

        if (ie){documentWidth  =document.body.offsetWidth/2+document.body.scrollLeft-20;

        documentHeight =document.body.offsetHeight/2+document.body.scrollTop-20;}

        else if (ns){documentWidth=window.innerWidth/2+window.pageXOffset-20;

        documentHeight=window.innerHeight/2+window.pageYOffset-20;}

        else if (w3){documentWidth=self.innerWidth/2+window.pageXOffset-20;

        documentHeight=self.innerHeight/2+window.pageYOffset-20;}

        adDiv.left=documentWidth-200;adDiv.top =documentHeight-200;

        setTimeout("showAd()",100);}else closeAd();

}

function closeAd(){

if (ie||w3)

adDiv.display="none";

else

adDiv.visibility ="hide";

}

onload=initAd;

</script>

<div id="sponsorAdDiv" style="visibility:hidden">

<table width="450" height="350" bgcolor="008000"><tr><td>

<table width="445" height="345" bgcolor="F0FFF0"><tr><td>

<center>welcome to www.CsrCode.cn!<BR><BR>這個窗口將在5秒后自動封鎖</center>

</td></tr></table></td></tr></table></div> 

</body>

</html>