javascript 操作cookie类

String.prototype.Trim = function()
   {
      return this.replace(/^\s+/g,"").replace(/\s+$/g,"");
   }
  
   function JSCookie()
   {
      this.GetCookie = function(key)
       {
         var cookie = document.cookie;
         var cookieArray = cookie.split(';');
         var getvalue = "";
        for(var i = 0;i<cookieArray.length;i++)
         {
            
            if(cookieArray[i].Trim().substr(0,key.length) == key)
             {
                 getvalue = cookieArray[i].Trim().substr(key.length + 1);
                break;
             }
         }

        return getvalue;
     };
    this.GetChild = function(cookiekey,childkey)
     {
         var child = this.GetCookie(cookiekey);
         var childs = child.split('&');
         var getvalue = "";
        
        for(var i = 0;i < childs.length;i++)
         {
            if(childs[i].Trim().substr(0,childkey.length) == childkey)
             {
                 getvalue = childs[i].Trim().substr(childkey.length + 1);
                break;
             }
         }
        return getvalue;
     };
    this.SetCookie = function(key,value,expire,domain,path)
     {
         var cookie = "";
        if(key != null && value != null)
             cookie += key + "=" + value + ";";
        if(expire != null)
             cookie += "expires=" + expire.toGMTString() + ";";
        if(domain != null)
             cookie += "domain=" + domain + ";";
        if(path != null)
             cookie += "path=" + path + ";";
         document.cookie = cookie;
     };
    this.Expire = function(key)
     {
         expire_time = new Date();
         expire_time.setFullYear(expire_time.getFullYear() - 1);
         var cookie = " " + key + "=e;expires=" + expire_time + ";"
         document.cookie = cookie;
     }
}

用法：
一、设置cookie
var cookie = new JSCookie();
//普通设置
cookie .SetCookie("key1","val1");

//过期时间为一年
var expire_time = new Date();
expire_time.setFullYear(expire_time.getFullYear() + 1);
cookie .SetCookie("key2","val2",expire_time);

//设置域及路径，带过期时间
cookie .SetCookie("key3","val3",expire_time,".cnblogs.com","/");

//设置带子键的cookie,子键分别是k1,k2,k3
cookie .SetCookie("key4","k1=1&k2=2&k3=3");

二、读取cookie
//简单获取
cookie .GetCookie("key1");
cookie .GetCookie("key2");
cookie .GetCookie("key3");
cookie .GetCookie("key4");
//获取key4的子键k1值
cookie .GetChild("key4","k1");

三、删除
cookie .Expire("key1");
cookie .Expire("key2");
cookie .Expire("key3");
cookie .Expire("key4");

转自：http://hi.baidu.com/ben2000/blog/item/82d946d01b2fd786a1ec9c51.html