Private void Form 1_Load (object sender, EventArgs e)

{

Com = new system. IO . ports . serial port()；

//Get all serial ports

Microsoft. Visual basic. devices.computerpc = new Microsoft. visual basic . devices . computer()；

Foreach (string s in PC. Port. Serial port name)

{

this . cbx port name . items . add；

}

}

is very good also

RegistryKey hklm = registry. Local machine;

RegistryKey hardware = hklm. OpenSubKey ("hardware");

RegistryKey device mapping = hardware. open subkey(" device map ")；

registry key serial comm = device map。 open subkey(" serial comm ")；

string[] s = SERIALCOMM。 GetValueNames()；