public void LoadOrderDetails(int orderId)
        {
            InventoryBL obj   = new InventoryBL();
            var         order = obj.GetOrderDetails(orderId);

            if (order != null)
            {
                txtCustName.Text  = order.Customer_Name;
                txtCustPhone.Text = order.Customer_Phone;
                txtAddress.Text   = order.Customer_Address;
                ddlProducts.SelectedItem.Value      = order.Product_Id.ToString();
                ddlNumberOfItems.SelectedItem.Value = order.Items_Count.ToString();
                txtCost.Text          = order.Product_Cost.ToString();
                txtAmount.Text        = order.Amount.ToString();
                txtGrossAmount.Text   = order.Gross_Amount.ToString();
                txtServiceCharge.Text = order.Service_Charge.ToString();
                txtVat.Text           = order.Vat_Charge.ToString();
                txtNetAmount.Text     = order.NetAmount.ToString();
            }
        }