private void button2_Click(object sender, EventArgs e)
        {
            string query = "delete from pessoas2015 where id = ?n ";
            try
            {
                cmd = new MySqlCommand(query, liga);
                cmd.Parameters.AddWithValue("?n", id);
                liga.Open();
                DialogResult result = MessageBox.Show("Deseja eliminar o registro na tabela?", "Eliminar registros", MessageBoxButtons.OKCancel, MessageBoxIcon.Question);
                if (result == DialogResult.OK)
                {
                    cmd.ExecuteNonQuery();
                    DisplayData();
                    ClearData();
                }
            }
            catch (MySqlException ex)
            {
                MessageBox.Show(ex.Message);
            }
            finally
            {
                liga.Close();
            }
        }