/*1.add(name,value,100); 添加一个cookie 
2.get(name); 
3.remove(name); 
Cookie.add("sk","ss",3); 
alert(cookie.get("sk")); 
Cookie.remove("sk"); 
*/
var Cookie=new function(){ 
//添加cookie 
this.add=function(name,value,hours){ 
var life=new Date().getTime(); 
life+=hours*1000*60; 
var cookieStr=name+"="+escape(value)+";expires="+new Date(life).toGMTString(); 
document.cookie=cookieStr; 
}; 
//获取cookie值 
this.get=function(name){ 
var cookies = document.cookie.split(";"); 
if(cookies.length>0){ 
var cookie=cookies[0].split("="); 
if(cookie[0]==name) 
return unescape(cookie[1]); 
} 
return null; 
}; 
//删除cookie 
this.remove=function(name){ 
var cookieStr=name+"="+escape('null')+";expires="+new Date().toGMTString(); 
document.cookie=cookieStr; 
}; 
}