Asp登陆验证

//
    public int adminPageUId = 0;
    public bool Login_CheckUser()
    {
        if (Session["user"] != null)
        {
            UserInfo user = (UserInfo)Session["user"];
            if (user.UserID == 0)
            {
                Response.Write("<script language='javascript' defer>alert('你还没有登录或长时间没有动作！');top.location.href='/index.aspx';</script>");
                Session.Remove("user");
                Page.Visible = false;
                return false; ;
            }
            else
            {
                //在此验证用户
                adminPageUId = user.UserID;
                return true;
            }
        }
        else
        {
            HttpCookie cook = Request.Cookies["user"];
            if (cook == null || cook["uid"]=="0")
            {
                Response.Write("<script language='javascript' defer>alert('你还没有登录或长时间没有动作！');top.location.href='/index.aspx';</script>");
                Page.Visible = false;
                return false;
            }
            else
            {
                //在此验证用户
                adminPageUId =Convert.ToInt32(cook["uid"]);
                return true;
            }
        }
    }