private void txtPartSearch_TextChanged(object sender, EventArgs e)
        {
            TextBox tb = (TextBox)sender;

            searchTerm = tb.Text;
            if (tb.Text.Length > 0)
            {
                dgPartsList.DataSource = partsService.SearchParts(searchTerm, searchOption);
            }
        }
        private void textBox2_TextChanged(object sender, EventArgs e)
        {
            TextBox tb = (TextBox)sender;

            listBox1.DisplayMember   = "ItemDescription";
            this.listBox1.DataSource = _partService.SearchParts(tb.Text, SearchOptions.Contains);
        }