利用javascript cookie实现记住提示框是否打开

var times = Math.ceil(Math.random()*100);
var settime =10000;
setInterval("setintval()",settime+times);
function setintval()
{
 
 var cookieval = getCookie("ifopen");
 //
 if( cookieval == undefined || cookieval == 'undefined' )
 {
  SetCookie("ifopen",'yes');
  alert( times+settime);
  
 }
 else
 {
  alert( cookieval );
 }
}

function closeit()
{
 var tmp = getCookie("ifopen");
 if( tmp  != undefined && tmp !='undefined' )
 {
  SetCookie("ifopen",'undefined');
 }
}

function SetCookie(name,value)
{
 var Days =10 ;// 300;
 var exp   = new Date();
 exp.setTime(exp.getTime() + Days*1000);
 document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString() + ";path=/";
}

function getCookie(name)
{
 var arr = document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));
 if(arr != null)
 {
  return unescape(arr[2]);
  return null;
 }
}

/*
关闭调用方法

关键操作

*/