protected void OnPagePropertiesChanging(object sender, PagePropertiesChangingEventArgs e)
        {
            (InvoiceList.FindControl("DataPager1") as DataPager).SetPageProperties(e.StartRowIndex, e.MaximumRows, false);

            // SEARCH BY NAME

            if (Convert.ToString(SearchDDL.SelectedValue) == "Name")
            {
                FilterInvoiceByName();
            }

            // SEARCH BY NOTE
            else if (Convert.ToString(SearchDDL.SelectedValue) == "No")
            {
                FilterInvoiceByNumber();
            }

            // NO SELECTION
            else
            {
                InvoiceListView();
            }
        }