protected void AddVouButton1_Click(object sender, EventArgs e)
        {
            if (Page.IsValid) // CustomValidator1.IsValid
            {
                // add voucher detail and retrieve list of voucher details not yet raised
                itemId = ItemCodeTextBox.Text;
                int    adjustedQty = Convert.ToInt32(AdjQtyTextBox.Text);
                string Remarks     = ReasonTextBox.Text;

                if (adjustedQty < 0)
                {
                    if (Math.Abs(adjustedQty) > Convert.ToInt32(InventoryBizLogic.GetInventoryItemQty(itemId)))
                    {
                        ScriptManager.RegisterStartupScript(this, this.GetType(), "alert", "alert('Please input a valid adjusted qty');", true);
                        this.Page_Load(null, null); // need this or else page won't add item the second time around
                    }

                    else
                    {
                        VoucherBizLogic.CreateVoucherDetail(itemId, adjustedQty, Remarks, (int)HttpContext.Current.Session["EmpID"]);// previously hardcoded employeeid as 1005; to retrieve employeeID from login later
                        BindGrid();

                        /* Change: 6-2-19 */
                        ChangeControlsVisibility("Raise");
                    }
                }

                else
                {
                    VoucherBizLogic.CreateVoucherDetail(itemId, adjustedQty, Remarks, (int)HttpContext.Current.Session["EmpID"]);// previously hardcoded employeeid as 1005; to retrieve employeeID from login later
                    BindGrid();

                    /* Change 6/2/19 */
                    ChangeControlsVisibility("Raise");
                }
            }
        }