protected void uiLinkButtonAddItem_Click(object sender, EventArgs e)
        {
            /* get items from stock */
            IStock.BLL.Items item = new IStock.BLL.Items();
            item.LoadByPrimaryKey(Convert.ToInt32(uiHiddenFieldCurrentItem.Value));
            if (!item.IsColumnNull("Quantity"))
            {
                if (item.Quantity == 0 || Convert.ToInt32(uiTextBoxQty.Text) > item.Quantity)
                {
                    ErrorDiv.Visible = true;
                    uiLabelError.Text = GetLocalResourceObject("ItemQtyError").ToString();
                    return;
                }
                item.Quantity -= Convert.ToInt32(uiTextBoxQty.Text);

            }
            else
            {
                ErrorDiv.Visible = true;
                uiLabelError.Text = GetLocalResourceObject("ItemQtyError").ToString();
                return;
            }
            item.Save();
            /* get items from stock */

            IStock.BLL.DeliveryOrderDetails detail = new IStock.BLL.DeliveryOrderDetails();
            detail.AddNew();
            detail.DeliveryOrderID = CurrentDeliveryOrder.DeliveryOrderID;
            detail.ItemID = Convert.ToInt32(uiHiddenFieldCurrentItem.Value);
            //detail.ItemID = Convert.ToInt32(uiDropDownListItems.SelectedValue);
            detail.Quantity = Convert.ToInt32(uiTextBoxQty.Text);
            detail.ItemPrice = decimal.Parse(uiTextBoxPrice.Text);
            detail.Save();

            decimal price = 0;
            if (!CurrentDeliveryOrder.IsColumnNull("Discount") && CurrentDeliveryOrder.Discount != 0)
            {
                price = detail.ItemPrice * detail.Quantity * (CurrentDeliveryOrder.Discount / 100);
            }
            else
            {
                price = detail.ItemPrice * detail.Quantity;
            }

            IStock.BLL.Clients client = new IStock.BLL.Clients();
            client.LoadByPrimaryKey(CurrentDeliveryOrder.ClientID);
            if (!client.IsColumnNull("StartCredit"))
                client.StartCredit += price;
            else
                client.StartCredit = price;
            client.Save();
            ErrorDiv.Visible = false;
            uiTextBoxItems.Text = "";
            uiTextBoxPrice.Text = "";
            uiTextBoxQty.Text = "";
            BindItems();
        }