//cookie operation
function _c(){}

//add cookie
_c.add = function(name,value,expireDays)
{
	var cookieString=name+"="+escape(value)+";path=/";
	if(expireDays>0){
		var date=new Date();
		date.setTime(date.getTime()+expireDays*24*3600*1000);
		cookieString=cookieString+";expires="+date.toGMTString();
	}
	document.cookie=cookieString;
};

//get cookie value
_c.get = function(name) 
{
	var strCookie=document.cookie;
	var arrCookie=strCookie.split("; ");
	for(var i=0;i<arrCookie.length;i++)
	{
		var arr=arrCookie[i].split("=");
		if(arr[0]==name){
			if(arr[1] == undefined)return ''; 
			return unescape(arr[1]);
		}
	}
	return "";
};

//del a cookie
_c.del = function(name)
{
	var date=new Date();
	date.setTime(date.getTime()-10000);
	document.cookie=name+"=v;expires="+date.toGMTString();
};