private void Form1_FormClosing(object sender, FormClosingEventArgs e) { if (COM4.IsOpen) { COM4.Close(); } }
private void button2_Click(object sender, EventArgs e) { try { if (COM4.IsOpen) { COM4.Close(); } status.Text = "закрыт"; } catch (System.IO.IOException) { status.Text = "ошибка"; MessageBox.Show("НЕТ"); } }