private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) { MySqlConnection Conn = new MySqlConnection(connectString); try { Console.WriteLine(comboBox1.SelectedItem.ToString()); var DataContacts = Utilitaire.comboType(comboBox1); dataGridView1.DataSource = DataContacts; } catch (Exception ex) { Console.WriteLine("toto"); } }