public List <Stock> GetAll(int centerId)
        {
            string query = "SELECT *FROM tbl_stock where centerId=" + centerId;

            ASqlConnection.Open();
            ASqlCommand    = new SqlCommand(query, ASqlConnection);
            ASqlDataReader = ASqlCommand.ExecuteReader();

            List <Stock> stockList = new List <Stock>();

            while (ASqlDataReader.Read())
            {
                MedicineDBGateway aGateway  = new MedicineDBGateway();;
                Stock             aStock    = new Stock();
                Medicine          aMedicine = aGateway.Find(Convert.ToInt32(ASqlDataReader["id"]));
                aStock.MedicineName = aMedicine.Name + "_" + aMedicine.MgMl;
                aStock.Quantity     = (int)ASqlDataReader["quantity"];

                stockList.Add(aStock);
            }
            ASqlDataReader.Close();
            ASqlConnection.Close();

            return(stockList);
        }