What is the best way to scan for COM ports in C#?

Question

Does C# provide an effective means of scanning the available COM ports? I would like to have a dropdown list in my application wherein the user can select one of the detected COM ports. Creating and populating the dropdown list is not a problem. I just need to know how to scan for the available COM ports using C#. I am using Microsoft Visual C# 2008 Express Edition. Thanks.

Answer 1

System.IO.Ports is the namespace you want.

SerialPort.GetPortNames will list all serial COM ports.

Unfortunately, parallel ports are not supported directly from C#, as they're very infrequently used except in legacy situations. That said, you can list them by querying the following registry key:

HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\PARALLEL PORTS

See the Microsoft.Win32 namespace for details.

Answer 2

Use WMI through the System.Management namespace. A quick Google finds this code:

using System;
using System.Management;

public class Foo 
{
    public static void Main() 
    {
       var instances = new ManagementClass("Win32_SerialPort").GetInstances();
       foreach ( ManagementObject port in instances )
       {
           Console.WriteLine("{0}: {1}", port["deviceid"], port["name"]);
       }
}