foreach (GridViewRow row in GridView1.Rows)
        {
            SqlCommand comm = new SqlCommand("DevStoreProc", conn);
            comm.CommandType = CommandType.StoredProcedure;


            float TotCost = float.Parse(row.Cells[0].Text);

            long invLineId = Convert.ToInt64(row.Cells[2].Text);
            string InvoiceNum = (ddlInvNum.SelectedItem.Text);
            int StockCode = Convert.ToInt32(row.Cells[4].Text);
            float qty = float.Parse(row.Cells[5].Text);
            float QtyOnHand = float.Parse(row.Cells[6].Text);
            DateTime DateSelected = Convert.ToDateTime(row.Cells[7].Text);
            float CurrCost = float.Parse(row.Cells[1].Text);

            float Value = float.Parse(txtValue.Text);
            float Sum = CurrCost + Value;



            comm.Parameters.Add(new SqlParameter("@SupplierName",  ddlSupplier.SelectedItem.Text));
            comm.Parameters.Add(new SqlParameter("@SupplierInvoice", ddlInvNum.SelectedItem.Text));


            comm.Parameters.AddWithValue("@StockCode", StockCode);
            comm.Parameters.AddWithValue("@Quantity", qty);
            comm.Parameters.AddWithValue("@QtyOnHand", QtyOnHand);
            comm.Parameters.AddWithValue("@InvoiceNumber", InvoiceNum);
            comm.Parameters.AddWithValue("@InvoiceLines", CurrCost);
            comm.Parameters.AddWithValue("@InvoiceTotal", TotCost);
            comm.Parameters.AddWithValue("@DateSelected", DateSelected);

            comm.Parameters.AddWithValue("@invLineId", invLineId);
            comm.Parameters.AddWithValue("@Value", Value);
            comm.Parameters.AddWithValue("@Sum", Sum);

            comm.ExecuteNonQuery();
        }
    }