C# winform 串口通信时检测电脑可用串口并显示

#region  全部串口和可用串口切换
private void button1_Click(object sender, EventArgs e)
{
switch (button1.Text)
{
case "可用串口":
try
{
button1.Text = "全部串口";
cb_port.Items.Clear();
string[] str = SerialPort.GetPortNames();
for (int i = 0; i < str.Length; i++)
{
cb_port.Items.Add(str[i]);
}
cb_port.SelectedIndex = 0;
}
catch (Exception)
{
MessageBox.Show("没有可用端口","提示");
}
break;
case "全部串口":
button1.Text = "可用串口";
cb_port.Items.Clear();
for (int i = 1; i <= 16; i++)
{
cb_port.Items.Add("COM"+i);
}
cb_port.SelectedIndex = 0;
break;
default:
MessageBox.Show("请选择可用串口");
break;
}
}
#endregion