一个IP只弹出一次代码

<script>

var cookieString = new String(document.cookie)

var cookieHeader = 'happy_pop=' //更换happy_pop为任意名称

var beginPosition = cookieString.indexOf(cookieHeader)

if (beginPosition <0){

window.open('http://你要弹出的ul','','top=0,left=0,width=787,height=

480,toolbar=yes,menubar=yes,scrollbars=yes,resizable=yes,location=yes,status=yes');

var Then = new Date()

Then.setTime(Then.getTime() + 12*60*60*1000 ) //同一ip设置过期时间，即多长间隔跳出一次

document.cookie = 'happy_pop=yes;expires='+ Then.toGMTString() //更换happy_pop和第4行一样的名称

}

</script>

sethome()

}

//-->

</script>