How do I get the friendly name of a COM port in Windows?

Question

I have a GSM modem connected via USB. The modem creates 2 serial ports. The first is automatically attached to the modem, the second shows in Device Manager as "HUAWEI Mobile Connect - 3G PC UI Interface (COM6)"

The second port is used to get vital information from the modem, such as signal quality; to send and receive text messages; and a whole host of other functions.

I am writing an application that will wrap up some of the features provided by the second port. What I need is a sure fire method of identifying which COM port is the spare one. Iterating the ports and checking a response to "ATE0" is not sufficient. The modem's port is usually the lower numbered one, and when a dial up connection is not active, it will respond to "ATE0" the same as the second port.

What I was thinking of doing is iterating the ports and checking their friendly name, as it shows in Device Manager. That way I can link the port in my application to the port labelled "HUAWEI Mobile Connect - 3G PC UI Interface (COM6)" in Device Manager. I've just not found any information yet that will allow me to get that name programmatically.

Answer 1

A long time ago I wrote a utility for a client to do just this, but for a GPS rather than a modem.

I have just looked at it, and bits that jump-out as being possibly helpful are:

    GUID guid = GUID_DEVCLASS_PORTS;

SP_DEVICE_INTERFACE_DATA interfaceData;
ZeroMemory(&interfaceData, sizeof(interfaceData));
interfaceData.cbSize = sizeof(interfaceData);

SP_DEVINFO_DATA devInfoData;
ZeroMemory(&devInfoData, sizeof(devInfoData));
devInfoData.cbSize = sizeof(devInfoData);

if(SetupDiEnumDeviceInfo(
 hDeviceInfo,   // Our device tree
 nDevice,   // The member to look for
 &devInfoData
 ))
{
 DWORD regDataType;

 BYTE hardwareId[300];
 if(SetupDiGetDeviceRegistryProperty(hDeviceInfo, &devInfoData, SPDRP_HARDWAREID, &regDataType, hardwareId, sizeof(hardwareId), NULL))
 {
...

(You call this bit in a loop with incrementing nDevice)

and then

BYTE friendlyName[300];
     if(SetupDiGetDeviceRegistryProperty(hDeviceInfo, &devInfoData, SPDRP_FRIENDLYNAME, NULL, friendlyName, sizeof(friendlyName), NULL))
     {
      strFriendlyNames += (LPCTSTR)friendlyName;
      strFriendlyNames += '\n';
     }

which finds the name of the device.

Hopefully that will help you in the right direction.

Answer 2

The information posted by http://stackoverflow.com/users/987/will-dean>Will Dean was most helpful. This is the code that eventually worked for me. Everything in the PInvoke class was taken verbatim from www.pinvoke.net. I did have to change a data type here or there to make it work (like when using an enum instead of a uint) but it should be easy to figure out.

        internal static string GetComPortByDescription(string Description)
        {
            string Result = string.Empty;
            Guid guid = PInvoke.GUID_DEVCLASS_PORTS;
            uint nDevice = 0;
            uint nBytes = 300;
            byte[] retval = new byte[nBytes];
            uint RequiredSize = 0;
            uint PropertyRegDataType = 0;

            PInvoke.SP_DEVINFO_DATA devInfoData = new PInvoke.SP_DEVINFO_DATA();
            devInfoData.cbSize = Marshal.SizeOf(typeof(PInvoke.SP_DEVINFO_DATA));

            IntPtr hDeviceInfo = PInvoke.SetupDiGetClassDevs(
                ref guid, 
                null, 
                IntPtr.Zero, 
                PInvoke.DIGCF.DIGCF_PRESENT);

            while (PInvoke.SetupDiEnumDeviceInfo(hDeviceInfo, nDevice++, ref devInfoData))
            {
                if (PInvoke.SetupDiGetDeviceRegistryProperty(
                        hDeviceInfo, 
                        ref devInfoData, 
                        PInvoke.SPDRP.SPDRP_FRIENDLYNAME,
                        out PropertyRegDataType, 
                        retval, 
                        nBytes, 
                        out RequiredSize))
                {
                    if (System.Text.Encoding.Unicode.GetString(retval).Substring(0, Description.Length).ToLower() ==
                        Description.ToLower())
                    {
                        string tmpstring = System.Text.Encoding.Unicode.GetString(retval);
                        Result = tmpstring.Substring(tmpstring.IndexOf("COM"),tmpstring.IndexOf(')') - tmpstring.IndexOf("COM"));
                    } // if retval == description
                } // if (PInvoke.SetupDiGetDeviceRegistryProperty( ... SPDRP_FRIENDLYNAME ...
            } // while (PInvoke.SetupDiEnumDeviceInfo(hDeviceInfo, nDevice++, ref devInfoData))

            PInvoke.SetupDiDestroyDeviceInfoList(hDeviceInfo);

            return Result;
        }

I think the line

Result = tmpstring.Substring(tmpstring.IndexOf("COM"),tmpstring.IndexOf(')') - tmpstring.IndexOf("COM"));

is a little clumsy, suggestions on how to clean it up would be appreciated.

Thanks for your help with this matter Will, without you, I'd still be searching google.

Answer 3

Glad it worked.

You could try:

Regex.Match(tmpstring, @"COM\s\d+").ToString()

for your string matching.

As .NET style points, I'd add a "using System.Text", and I wouldn't start local variable names with capitals, and if I was feeling really virtuous, I would probably put the SetupDiDestroyDeviceInfoList in a finally{} clause.

Answer 4

After you determine a Serial Port device is the one you want (by looking at its Friendly Name, by checking its parent device etc.), the proper way to get the port's name would probably be:

• invoke SetupDiOpenDevRegKey(hDevInfo, devInfoData, DICS_FLAG_GLOBAL, 0, DIREG_DEV, KEY_READ) to get the HKEY to the so-called device key
• query this registry key for the REG_SZ value "PortName"
• don't forget to close the HKEY :)

However, this might require so much interop in C# it's not even funny, so I don't blame you if you keep to the string parsing solution.

Answer 5

Hi,

I'm not a C# expert by any means, but I've mixed C# and VB code before and in the current project I'm working on as well. When I try the above code I'm getting PInvoke namespace errors and can't for the life of google figure out what to include.

Error 2 The type or namespace name 'PInvoke' could not be found (are you missing a using directive or an assembly reference?)

Jacob

I answered my own question and lost some more hair in the process. I had to create a public class called PInvoke that has all the PInvoke prototypes so to get the code to work as shown... I'm including it here for the benefit of others:

Most of (if not all of these proto's came from pinvoke.net)

enter code here
public class PInvoke
{
    public class GUID_DEVCLASS
    {

        public static readonly Guid GUID_DEVCLASS_1394 = new Guid("{0x6bdd1fc1, 0x810f, 0x11d0, {0xbe, 0xc7, 0x08, 0x00, 0x2b, 0xe2, 0x09, 0x2f}}");
        public static readonly Guid GUID_DEVCLASS_1394DEBUG = new Guid("{0x66f250d6, 0x7801, 0x4a64, {0xb1, 0x39, 0xee, 0xa8, 0x0a, 0x45, 0x0b, 0x24}}");
        public static readonly Guid GUID_DEVCLASS_61883 = new Guid("{0x7ebefbc0, 0x3200, 0x11d2, {0xb4, 0xc2, 0x00, 0xa0, 0xc9, 0x69, 0x7d, 0x07}}");
        public static readonly Guid GUID_DEVCLASS_ADAPTER = new Guid("{0x4d36e964, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_APMSUPPORT = new Guid("{0xd45b1c18, 0xc8fa, 0x11d1, {0x9f, 0x77, 0x00, 0x00, 0xf8, 0x05, 0xf5, 0x30}}");
        public static readonly Guid GUID_DEVCLASS_AVC = new Guid("{0xc06ff265, 0xae09, 0x48f0, {0x81, 0x2c, 0x16, 0x75, 0x3d, 0x7c, 0xba, 0x83}}");
        public static readonly Guid GUID_DEVCLASS_BATTERY = new Guid("{0x72631e54, 0x78a4, 0x11d0, {0xbc, 0xf7, 0x00, 0xaa, 0x00, 0xb7, 0xb3, 0x2a}}");
        public static readonly Guid GUID_DEVCLASS_BIOMETRIC = new Guid("{0x53d29ef7, 0x377c, 0x4d14, {0x86, 0x4b, 0xeb, 0x3a, 0x85, 0x76, 0x93, 0x59}}");
        public static readonly Guid GUID_DEVCLASS_BLUETOOTH = new Guid("{0xe0cbf06c, 0xcd8b, 0x4647, {0xbb, 0x8a, 0x26, 0x3b, 0x43, 0xf0, 0xf9, 0x74}}");
        public static readonly Guid GUID_DEVCLASS_CDROM = new Guid("{0x4d36e965, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_COMPUTER = new Guid("{0x4d36e966, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_DECODER = new Guid("{0x6bdd1fc2, 0x810f, 0x11d0, {0xbe, 0xc7, 0x08, 0x00, 0x2b, 0xe2, 0x09, 0x2f}}");
        public static readonly Guid GUID_DEVCLASS_DISKDRIVE = new Guid("{0x4d36e967, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_DISPLAY = new Guid("{0x4d36e968, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_DOT4 = new Guid("{0x48721b56, 0x6795, 0x11d2, {0xb1, 0xa8, 0x00, 0x80, 0xc7, 0x2e, 0x74, 0xa2}}");
        public static readonly Guid GUID_DEVCLASS_DOT4PRINT = new Guid("{0x49ce6ac8, 0x6f86, 0x11d2, {0xb1, 0xe5, 0x00, 0x80, 0xc7, 0x2e, 0x74, 0xa2}}");
        public static readonly Guid GUID_DEVCLASS_ENUM1394 = new Guid("{0xc459df55, 0xdb08, 0x11d1, {0xb0, 0x09, 0x00, 0xa0, 0xc9, 0x08, 0x1f, 0xf6}}");
        public static readonly Guid GUID_DEVCLASS_FDC = new Guid("{0x4d36e969, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_FLOPPYDISK = new Guid("{0x4d36e980, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_GPS = new Guid("{0x6bdd1fc3, 0x810f, 0x11d0, {0xbe, 0xc7, 0x08, 0x00, 0x2b, 0xe2, 0x09, 0x2f}}");
        public static readonly Guid GUID_DEVCLASS_HDC = new Guid("{0x4d36e96a, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_HIDCLASS = new Guid("{0x745a17a0, 0x74d3, 0x11d0, {0xb6, 0xfe, 0x00, 0xa0, 0xc9, 0x0f, 0x57, 0xda}}");
        public static readonly Guid GUID_DEVCLASS_IMAGE = new Guid("{0x6bdd1fc6, 0x810f, 0x11d0, {0xbe, 0xc7, 0x08, 0x00, 0x2b, 0xe2, 0x09, 0x2f}}");
        public static readonly Guid GUID_DEVCLASS_INFINIBAND = new Guid("{0x30ef7132, 0xd858, 0x4a0c, {0xac, 0x24, 0xb9, 0x02, 0x8a, 0x5c, 0xca, 0x3f}}");
        public static readonly Guid GUID_DEVCLASS_INFRARED = new Guid("{0x6bdd1fc5, 0x810f, 0x11d0, {0xbe, 0xc7, 0x08, 0x00, 0x2b, 0xe2, 0x09, 0x2f}}");
        public static readonly Guid GUID_DEVCLASS_KEYBOARD = new Guid("{0x4d36e96b, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_LEGACYDRIVER = new Guid("{0x8ecc055d, 0x047f, 0x11d1, {0xa5, 0x37, 0x00, 0x00, 0xf8, 0x75, 0x3e, 0xd1}}");
        public static readonly Guid GUID_DEVCLASS_MEDIA = new Guid("{0x4d36e96c, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_MEDIUM_CHANGER = new Guid("{0xce5939ae, 0xebde, 0x11d0, {0xb1, 0x81, 0x00, 0x00, 0xf8, 0x75, 0x3e, 0xc4}}");
        public static readonly Guid GUID_DEVCLASS_MODEM = new Guid("{0x4d36e96d, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_MONITOR = new Guid("{0x4d36e96e, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_MOUSE = new Guid("{0x4d36e96f, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_MTD = new Guid("{0x4d36e970, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_MULTIFUNCTION = new Guid("{0x4d36e971, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_MULTIPORTSERIAL = new Guid("{0x50906cb8, 0xba12, 0x11d1, {0xbf, 0x5d, 0x00, 0x00, 0xf8, 0x05, 0xf5, 0x30}}");
        public static readonly Guid GUID_DEVCLASS_NET = new Guid("{0x4d36e972, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_NETCLIENT = new Guid("{0x4d36e973, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_NETSERVICE = new Guid("{0x4d36e974, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_NETTRANS = new Guid("{0x4d36e975, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_NODRIVER = new Guid("{0x4d36e976, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_PCMCIA = new Guid("{0x4d36e977, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_PNPPRINTERS = new Guid("{0x4658ee7e, 0xf050, 0x11d1, {0xb6, 0xbd, 0x00, 0xc0, 0x4f, 0xa3, 0x72, 0xa7}}");
        public static readonly Guid GUID_DEVCLASS_PORTS = new Guid("{0x4d36e978, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_PRINTER = new Guid("{0x4d36e979, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_PRINTERUPGRADE = new Guid("{0x4d36e97a, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_PROCESSOR = new Guid("{0x50127dc3, 0x0f36, 0x415e, {0xa6, 0xcc, 0x4c, 0xb3, 0xbe, 0x91, 0x0B, 0x65}}");
        public static readonly Guid GUID_DEVCLASS_SBP2 = new Guid("{0xd48179be, 0xec20, 0x11d1, {0xb6, 0xb8, 0x00, 0xc0, 0x4f, 0xa3, 0x72, 0xa7}}");
        public static readonly Guid GUID_DEVCLASS_SCSIADAPTER = new Guid("{0x4d36e97b, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_SECURITYACCELERATOR = new Guid("{0x268c95a1, 0xedfe, 0x11d3, {0x95, 0xc3, 0x00, 0x10, 0xdc, 0x40, 0x50, 0xa5}}");
        public static readonly Guid GUID_DEVCLASS_SMARTCARDREADER = new Guid("{0x50dd5230, 0xba8a, 0x11d1, {0xbf, 0x5d, 0x00, 0x00, 0xf8, 0x05, 0xf5, 0x30}}");
        public static readonly Guid GUID_DEVCLASS_SOUND = new Guid("{0x4d36e97c, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_SYSTEM = new Guid("{0x4d36e97d, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_TAPEDRIVE = new Guid("{0x6d807884, 0x7d21, 0x11cf, {0x80, 0x1c, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_UNKNOWN = new Guid("{0x4d36e97e, 0xe325, 0x11ce, {0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}}");
        public static readonly Guid GUID_DEVCLASS_USB = new Guid("{0x36fc9e60, 0xc465, 0x11cf, {0x80, 0x56, 0x44, 0x45, 0x53, 0x54, 0x00, 0x00}}");
        public static readonly Guid GUID_DEVCLASS_VOLUME = new Guid("{0x71a27cdd, 0x812a, 0x11d0, {0xbe, 0xc7, 0x08, 0x00, 0x2b, 0xe2, 0x09, 0x2f}}");
        public static readonly Guid GUID_DEVCLASS_VOLUMESNAPSHOT = new Guid("{0x533c5b84, 0xec70, 0x11d2, {0x95, 0x05, 0x00, 0xc0, 0x4f, 0x79, 0xde, 0xaf}}");
        public static readonly Guid GUID_DEVCLASS_WCEUSBS = new Guid("{0x25dbce51, 0x6c8f, 0x4a72, {0x8a, 0x6d, 0xb5, 0x4c, 0x2b, 0x4f, 0xc8, 0x35}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_ACTIVITYMONITOR = new Guid("{0xb86dff51, 0xa31e, 0x4bac, {0xb3, 0xcf, 0xe8, 0xcf, 0xe7, 0x5c, 0x9f, 0xc2}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_UNDELETE = new Guid("{0xfe8f1572, 0xc67a, 0x48c0, {0xbb, 0xac, 0x0b, 0x5c, 0x6d, 0x66, 0xca, 0xfb}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_ANTIVIRUS = new Guid("{0xb1d1a169, 0xc54f, 0x4379, {0x81, 0xdb, 0xbe, 0xe7, 0xd8, 0x8d, 0x74, 0x54}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_REPLICATION = new Guid("{0x48d3ebc4, 0x4cf8, 0x48ff, {0xb8, 0x69, 0x9c, 0x68, 0xad, 0x42, 0xeb, 0x9f}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_CONTINUOUSBACKUP = new Guid("{0x71aa14f8, 0x6fad, 0x4622, {0xad, 0x77, 0x92, 0xbb, 0x9d, 0x7e, 0x69, 0x47}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_CONTENTSCREENER = new Guid("{0x3e3f0674, 0xc83c, 0x4558, {0xbb, 0x26, 0x98, 0x20, 0xe1, 0xeb, 0xa5, 0xc5}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_QUOTAMANAGEMENT = new Guid("{0x8503c911, 0xa6c7, 0x4919, {0x8f, 0x79, 0x50, 0x28, 0xf5, 0x86, 0x6b, 0x0c}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_SYSTEMRECOVERY = new Guid("{0x2db15374, 0x706e, 0x4131, {0xa0, 0xc7, 0xd7, 0xc7, 0x8e, 0xb0, 0x28, 0x9a}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_CFSMETADATASERVER = new Guid("{0xcdcf0939, 0xb75b, 0x4630, {0xbf, 0x76, 0x80, 0xf7, 0xba, 0x65, 0x58, 0x84}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_HSM = new Guid("{0xd546500a, 0x2aeb, 0x45f6, {0x94, 0x82, 0xf4, 0xb1, 0x79, 0x9c, 0x31, 0x77}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_COMPRESSION = new Guid("{0xf3586baf, 0xb5aa, 0x49b5, {0x8d, 0x6c, 0x05, 0x69, 0x28, 0x4c, 0x63, 0x9f}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_ENCRYPTION = new Guid("{0xa0a701c0, 0xa511, 0x42ff, {0xaa, 0x6c, 0x06, 0xdc, 0x03, 0x95, 0x57, 0x6f}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_PHYSICALQUOTAMANAGEMENT = new Guid("{0x6a0a8e78, 0xbba6, 0x4fc4, {0xa7, 0x09, 0x1e, 0x33, 0xcd, 0x09, 0xd6, 0x7e}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_OPENFILEBACKUP = new Guid("{0xf8ecafa6, 0x66d1, 0x41a5, {0x89, 0x9b, 0x66, 0x58, 0x5d, 0x72, 0x16, 0xb7}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_SECURITYENHANCER = new Guid("{0xd02bc3da, 0x0c8e, 0x4945, {0x9b, 0xd5, 0xf1, 0x88, 0x3c, 0x22, 0x6c, 0x8c}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_COPYPROTECTION = new Guid("{0x89786ff1, 0x9c12, 0x402f, {0x9c, 0x9e, 0x17, 0x75, 0x3c, 0x7f, 0x43, 0x75}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_SYSTEM = new Guid("{0x5d1b9aaa, 0x01e2, 0x46af, {0x84, 0x9f, 0x27, 0x2b, 0x3f, 0x32, 0x4c, 0x46}}");
        public static readonly Guid GUID_DEVCLASS_FSFILTER_INFRASTRUCTURE = new Guid("{0xe55fa6f9, 0x128c, 0x4d04, {0xab, 0xab, 0x63, 0x0c, 0x74, 0xb1, 0x45, 0x3a}}");
    }

    /// <summary>
    /// Flags controlling what is included in the device information set built by SetupDiGetClassDevs
    /// </summary>
    [Flags]
    public enum DIGCF : uint
    {
        DIGCF_DEFAULT = 0x00000001,    // only valid with DIGCF_DEVICEINTERFACE
        DIGCF_PRESENT = 0x00000002,
        DIGCF_ALLCLASSES = 0x00000004,
        DIGCF_PROFILE = 0x00000008,
        DIGCF_DEVICEINTERFACE = 0x00000010,
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct SP_DEVINFO_DATA
    {
        public UInt32 cbSize;
        public Guid ClassGuid;
        public UInt32 DevInst;
        public IntPtr Reserved;
    }

    [DllImport("setupapi.dll", CharSet = CharSet.Auto)]
    public static extern IntPtr SetupDiGetClassDevs(ref Guid ClassGuid,
                                             [MarshalAs(UnmanagedType.LPTStr)] string Enumerator,
                                             IntPtr hwndParent,
                                             UInt32 Flags
                                            );
    [DllImport(@"setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public static extern bool SetupDiDestroyDeviceInfoList(IntPtr hDevInfo);

    public enum SPDRP
    {
        SPDRP_DEVICEDESC = 0x00000000,
        SPDRP_HARDWAREID = 0x00000001,
        SPDRP_COMPATIBLEIDS = 0x00000002,
        SPDRP_NTDEVICEPATHS = 0x00000003,
        SPDRP_SERVICE = 0x00000004,
        SPDRP_CONFIGURATION = 0x00000005,
        SPDRP_CONFIGURATIONVECTOR = 0x00000006,
        SPDRP_CLASS = 0x00000007,
        SPDRP_CLASSGUID = 0x00000008,
        SPDRP_DRIVER = 0x00000009,
        SPDRP_CONFIGFLAGS = 0x0000000A,
        SPDRP_MFG = 0x0000000B,
        SPDRP_FRIENDLYNAME = 0x0000000C,
        SPDRP_LOCATION_INFORMATION = 0x0000000D,
        SPDRP_PHYSICAL_DEVICE_OBJECT_NAME = 0x0000000E,
        SPDRP_CAPABILITIES = 0x0000000F,
        SPDRP_UI_NUMBER = 0x00000010,
        SPDRP_UPPERFILTERS = 0x00000011,
        SPDRP_LOWERFILTERS = 0x00000012,
        SPDRP_MAXIMUM_PROPERTY = 0x00000013,
    }

    /// <summary>
    /// The SetupDiGetDeviceRegistryProperty function retrieves the specified device property.
    /// This handle is typically returned by the SetupDiGetClassDevs or SetupDiGetClassDevsEx function.
    /// </summary>
    /// <param Name="DeviceInfoSet">Handle to the device information set that contains the interface and its underlying device.</param>
    /// <param Name="DeviceInfoData">Pointer to an SP_DEVINFO_DATA structure that defines the device instance.</param>
    /// <param Name="Property">Device property to be retrieved. SEE MSDN</param>
    /// <param Name="PropertyRegDataType">Pointer to a variable that receives the registry data Type. This parameter can be NULL.</param>
    /// <param Name="PropertyBuffer">Pointer to a buffer that receives the requested device property.</param>
    /// <param Name="PropertyBufferSize">Size of the buffer, in bytes.</param>
    /// <param Name="RequiredSize">Pointer to a variable that receives the required buffer size, in bytes. This parameter can be NULL.</param>
    /// <returns>If the function succeeds, the return value is nonzero.</returns>
    [DllImport("setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public static extern bool SetupDiGetDeviceRegistryProperty(
        IntPtr DeviceInfoSet,
        ref SP_DEVINFO_DATA DeviceInfoData,
        uint Property,
        out UInt32 PropertyRegDataType,
        byte[] PropertyBuffer,
        uint PropertyBufferSize,
        out UInt32 RequiredSize
        );

    [DllImport("setupapi.dll", SetLastError = true)]
    public static extern bool SetupDiEnumDeviceInfo(IntPtr DeviceInfoSet, uint MemberIndex, ref SP_DEVINFO_DATA DeviceInfoData);

}