protected void ui_save_button_Click(object sender, EventArgs e)
        {
            StationeryController sationeryController = new StationeryController();

            Stationery stationery = new Stationery();
            int stationery_id;

            //getting hidden field id
            if (int.TryParse(ui_id_hiddenfield.Value, out stationery_id))
            {
                stationery.id = Convert.ToInt32(ui_id_hiddenfield.Value);
                stationery = sationeryController.actionGetStationeryByID(stationery.id);
            }

            //fields validation
            if (String.IsNullOrEmpty(ui_code_textbox.Text) ||
                String.IsNullOrEmpty(ui_name_textbox.Text) ||
                String.IsNullOrEmpty(ui_reorderlevel_textbox.Text) ||
                String.IsNullOrEmpty(ui_reorderquantity_textbox.Text) ||
                String.IsNullOrEmpty(ui_uom_textbox.Text) ||
                String.IsNullOrEmpty(ui_price_textbox.Text)
                )
            {
                Response.Cookies.Add(new HttpCookie("flash_message", "Field(s) marked with * can't be empty.") { Path = "/" });
                Response.Cookies.Add(new HttpCookie("flash_css", "alert alert-error") { Path = "/" });
                return;
                //String idstring = (supplier.id > 0) ? ("?id="+supplier.id) : ("");
                //Response.Redirect("~/StoreClerk/SupplierDetail.aspx"+idstring);
            }

            try
            {
                stationery.reorder_level = Convert.ToInt32(ui_reorderlevel_textbox.Text);
                stationery.reorder_quantity = Convert.ToInt32(ui_reorderquantity_textbox.Text);
                stationery.price = Convert.ToDouble(ui_price_textbox.Text);
            }
            catch (Exception ex)
            {
                Response.Cookies.Add(new HttpCookie("flash_message", "Price Reorder Level and Reorder Quantity only allow numbers." ) { Path = "/" });
                Response.Cookies.Add(new HttpCookie("flash_css", "alert alert-error") { Path = "/" });
                return;
            }

            //setting up object
            //setting up object
            stationery.code = ui_code_textbox.Text;
            stationery.stationery_name = ui_name_textbox.Text;
            stationery.category = Convert.ToInt32(ui_category_dropdown.SelectedValue);
            stationery.reorder_level = Convert.ToInt32(ui_reorderlevel_textbox.Text);
            stationery.reorder_quantity = Convert.ToInt32(ui_reorderquantity_textbox.Text);
            stationery.unit_of_measure = ui_uom_textbox.Text;
            stationery.bin = ui_binnum_textbox.Text;

            //stationery.quantity_in_stock = Convert.ToInt32(ui_quantityinstock_label.Text);
            //stationery.pending_quantity_to_distribute = Convert.ToInt32(ui_pendingquantity_label.Text);

            if (Page.IsPostBack) {

            }

            stationery.first_supplier = Convert.ToInt32(ui_firstsupplier_dropdown.SelectedItem.Value);
            stationery.second_supplier = Convert.ToInt32(ui_secondsupplier_dropdown.SelectedItem.Value);
            stationery.third_supplier = Convert.ToInt32(ui_thirdsupplier_dropdown.SelectedItem.Value);

            //stationery.first_supplier = 5;
            //stationery.second_supplier = 4;
            //stationery.third_supplier = 1;

            //updating db;
            Message message;
            if (stationery.id > 0)
            {
                message = sationeryController.actionUpdateStationery(stationery);
            }
            else
            {
                stationery.quantity_in_stock = 0;
                stationery.pending_quantity_to_distribute = 0;
                message = sationeryController.actionCreateStationery(stationery);
            }

            //redirecting
            if (message.condition)
            {
                Response.Cookies.Add(new HttpCookie("flash_message", "Successfully Saved.") { Path = "/" });
                Response.Cookies.Add(new HttpCookie("flash_css", "alert alert-success") { Path = "/" });
                Response.Redirect("~/StoreClerk/StatoneryDetail.aspx?id=" + stationery.id);
            }
            else
            {
                Response.Cookies.Add(new HttpCookie("flash_message", message.message) { Path = "/" });
                Response.Cookies.Add(new HttpCookie("flash_css", "alert alert-error") { Path = "/" });
                Response.Redirect("~/StoreClerk/StatoneryDetail.aspx?id=" + stationery.id);
            }
        }