JS实现5秒钟自动封锁div层的方法
本文实例讲述了JS实现5秒钟自动封锁div层的方法。分享给大家供大家参考。具体实现方法如下：
<html>
<head>
<title>JS实现5秒钟自动封锁div层</title>
<styletype="text/css">
<!--
#sponsorAdDiv{position:absolute;height:1;width:1;top:0;left:0;}
-->
</style>
</head>
<body>
<SCRIPTLANGUAGE="JavaScript1.2">
adTime=5; //封锁窗口期待的时间
chanceAd=1;
varns=(document.layers);
varie=(document.all);
varw3=(document.getElementById&&!ie);
adCount=0;
functioninitAd(){
if(!ns&&!ie&&!w3)return;
if(ie) adDiv=eval('document.all.sponsorAdDiv.style');
elseif(ns) adDiv=eval('document.layers["sponsorAdDiv"]');
elseif(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();
}
functionshowAd(){
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;}
elseif(ns){documentWidth=window.innerWidth/2+window.pageXOffset-20;
documentHeight=window.innerHeight/2+window.pageYOffset-20;}
elseif(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);}elsecloseAd();
}
functioncloseAd(){
if(ie||w3)
adDiv.display="none";
else
adDiv.visibility="hide";
}
onload=initAd;
</script>
<divid="sponsorAdDiv"style="visibility:hidden">
<tablewidth="450"height="350"bgcolor="008000"><tr><td>
<tablewidth="445"height="345"bgcolor="F0FFF0"><tr><td>
<center>welcometowww.CsrCode.cn!<BR><BR>这个窗口将在5秒后自动封锁</center>
</td></tr></table></td></tr></table></div>
</body>
</html>
希望本文所述对大家的javascript程序设计有所帮助。