BC_Logger_control.Form1.button_refresh_Click C# (CSharp) Method

        private void button_refresh_Click(object sender, EventArgs e)
        {
            comboBox_portName.Items.Clear();
            comboBox_portName.Items.Add("None");
            foreach (string portname in SerialPort.GetPortNames())
            {
                comboBox_portName.Items.Add(portname); //добавить порт в список
            }
            if (comboBox_portName.Items.Count == 1)
            {
                comboBox_portName.SelectedIndex = 0;
                button_openPort.Enabled = false;
            }
            else comboBox_portName.SelectedIndex = 0;

            Hashtable PortNames = new Hashtable();
            string[] ports = System.IO.Ports.SerialPort.GetPortNames();
            if (ports.Length == 0)
            {
                textBox_terminal.Text += "ERROR: No COM ports exist\n\r";
            }
            else
            {
                PortNames = BuildPortNameHash(ports);
                foreach (String s in PortNames.Keys)
                {
                    textBox_terminal.Text += "\n\r" + PortNames[s] + ": " + s + "\n\r";
                }
            }
        }