internal void updateInvoice(Invoice invoice) { try { string sql = "UPDATE Invoice SET Total = @total, Miles = @miles WHERE InvoiceId = @invoiceId"; conn = new MySql.Data.MySqlClient.MySqlConnection(myConnectionString); MySqlCommand command = new MySqlCommand(sql, conn); command.Parameters.AddWithValue("total", invoice.getTotal()); command.Parameters.AddWithValue("miles", invoice.getMiles()); command.Parameters.AddWithValue("invoiceId", invoice.getInvoiceId()); conn.Open(); command.ExecuteNonQuery(); } catch (Exception ex) { MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); } finally { conn.Close(); } }