void Session_Start(object sender, EventArgs e)
        {
            Session.Timeout = 150;
            Application.Lock();
            Application["visitors_online"] = Convert.ToInt32(Application["visitors_online"]) + 1;
            Application.UnLock();
            try
            {
                // DataBindSQL mThongKe = new DataBindSQL();
                // DataTable dtb = mThongKe.TableThongKe();

                Web_Shop_SettingIphoneEntities connect_entity = new Web_Shop_SettingIphoneEntities();

                var dtb = connect_entity.spThongKe_Edit().ToList();

                if (dtb.Count > 0)
                {
                    Application["HomNay"]     = long.Parse("0" + dtb[0].HomNay).ToString("#,###");
                    Application["HomQua"]     = long.Parse("0" + dtb[0].HomQua).ToString("#,###");
                    Application["TuanNay"]    = long.Parse("0" + dtb[0].TuanNay).ToString("#,###");
                    Application["TuanTruoc"]  = long.Parse("0" + dtb[0].TuanTruoc).ToString("#,###");
                    Application["ThangNay"]   = long.Parse("0" + dtb[0].ThangNay).ToString("#,###");
                    Application["ThangTruoc"] = long.Parse("0" + dtb[0].ThangTruoc).ToString("#,###");
                    Application["NamNay"]     = long.Parse("0" + dtb[0].NamNay).ToString("#,###");
                    Application["NamTruoc"]   = long.Parse("0" + dtb[0].NamTruoc).ToString("#,###");
                    Application["TatCa"]      = long.Parse("0" + dtb[0].TatCa).ToString("#,###");
                }
            }
            catch { }
        }
        /// <summary>
        /// Ham su ly khi goi ham: FormsAuthentication.SetAuthCookie(account, true or false);
        /// </summary>
        /// <param name="username">account</param>
        /// <returns>tra ve quyen cua tai khoan</returns>
        public override string[] GetRolesForUser(string username)
        {
            ////-----------------ket noi voi database de lay quyen cua tai khoan-----------------
            Web_Shop_SettingIphoneEntities db = new Web_Shop_SettingIphoneEntities(); //tao ket noi voi database

            try
            {
                var account = db.Users.Single(x => x.Username.Equals(username)); //tuong duong voi cau lenh "Select Top 1 From Accounts Where NameAccount = username"
                if (account != null)                                             //neu tim thay tai khoan
                {
                    return(new String[] { account.Role });                       //tra ve quyen cua nguoi dung
                }
                else
                {
                    return new String[] { }
                };                           //new khong tim thay tai khoan thi gan quyen bang null
            }
            catch
            {
                return(new String[] { }); //new khong tim thay tai khoan TRONG CSDL thi gan quyen bang null
            }
        }