Question

When I connect to a windows mobile device from the PC using the RAPI API I can get its device ID like so:

using (RemoteDeviceManager r = new RemoteDeviceManager())
{
     using (RemoteDevice dev = r.Devices.FirstConnectedDevice)
     {
         //dev.DeviceId; <--the id
     }
}

How can I get the same ‘DeviceId’ value on the device itself in compact framework?

Answer 1

Microsoft published a library article back in 2003 on Retrieving the Windows CE Device ID with the Microsoft .NET Compact Framework that I have been using with success.

[DllImport("coredll.dll")]
private static extern bool KernelIoControl(Int32 IoControlCode, IntPtr InputBuffer, Int32 InputBufferSize, byte[] OutputBuffer, Int32 OutputBufferSize, ref Int32 BytesReturned);

private static string GetDeviceID() {
  // Reference: http://msdn.microsoft.com/en-us/library/aa446562.aspx
  byte[] data = new byte[256];
  Int32 OutputBufferSize, BytesReturned;
  OutputBufferSize = data.Length;
  BytesReturned = 0;
  // Call KernelIoControl passing the previously defined IOCTL_HAL_GET_DEVICEID parameter
  // We don’t need to pass any input buffers to this call
  // so InputBuffer and InputBufferSize are set to their null values
  bool retVal = KernelIoControl(IOCTL_HAL_GET_DEVICEID, IntPtr.Zero, 0, data, OutputBufferSize, ref BytesReturned);
  // If the request failed, exit the method now
  if (retVal) {
    // Examine the OutputBuffer byte array to find the start of the 
    // Preset ID and Platform ID, as well as the size of the PlatformID. 
    // PresetIDOffset – The number of bytes the preset ID is offset from the beginning of the structure
    // PlatformIDOffset - The number of bytes the platform ID is offset from the beginning of the structure
    // PlatformIDSize - The number of bytes used to store the platform ID
    // Use BitConverter.ToInt32() to convert from byte[] to int
    Int32 PresetIDOffset = BitConverter.ToInt32(data, 4);
    Int32 PlatformIDOffset = BitConverter.ToInt32(data, 0xc);
    Int32 PlatformIDSize = BitConverter.ToInt32(data, 0x10);

    // Convert the Preset ID segments into a string so they can be 
    // displayed easily.
    StringBuilder sb = new StringBuilder();
    sb.Append(String.Format("{0:X8}-{1:X4}-{2:X4}-{3:X4}-",
         BitConverter.ToInt32(data, PresetIDOffset),
         BitConverter.ToInt16(data, PresetIDOffset + 4),
         BitConverter.ToInt16(data, PresetIDOffset + 6),
         BitConverter.ToInt16(data, PresetIDOffset + 8)));

    // Break the Platform ID down into 2-digit hexadecimal numbers
    // and append them to the Preset ID. This will result in a 
    // string-formatted Device ID
    for (int i = PlatformIDOffset; i < PlatformIDOffset + PlatformIDSize; i++) {
      sb.Append(String.Format("{0:X2}", data[i]));
    }
    // return the Device ID string
    return sb.ToString();
  }
  return null;
}