/// <summary>
        /// Get all categories
        /// </summary>
        /// <returns></returns>
        public IList <MenuItemCategory> GetCategories()
        {
            if (waiterUserContext == null)
            {
                return(null);
            }

            try
            {
                return(WaiterDataAccess.GetMenuItemCategories(waiterUserContext.Id).ToList());
            }
            catch
            {
                throw new Exception("Problem with DB");
            }
        }