public SalesModelList GetSalesByCategory(string categoryName, string orderYear)
        {
            SalesModelList salesResults = new SalesModelList();

            htParams["@CategoryName"] = categoryName;
            htParams["@OrdYear"]      = orderYear;

            try
            {
                DataSet ds = results.GetSPDataSet("[dbo].[SalesByCategory]", htParams);
            }
            catch (Exception)
            {
                throw;
            }

            return(salesResults);
        }
        public SalesModelList GetSalesByYear(DateTime beginningDate, DateTime endingDate)
        {
            SalesModelList salesResults = new SalesModelList();

            htParams["@Beginning_Date"] = beginningDate;
            htParams["@Ending_Date"]    = endingDate;

            try
            {
                DataSet ds = results.GetSPDataSet("[dbo].[Sales by Year]", htParams);
                salesResults = MappingSalesByYear(ds);
            }
            catch (Exception)
            {
                throw;
            }

            return(salesResults);
        }