public bool Close(string userId) { bool flag = false; UserSessionBE objBE = objUserSessionBL.GetByUser(Guid.Parse(userId)); if (objBE != null) { objBE.Validity = App.getDate(); this.objUserSessionBL.Update(objBE); ApplicationInstance.DeleteCache <Principal>(Convert.ToString(objBE.UserId.Value)); flag = true; } return(flag); }