How to: Get the Device ID and Name
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To get the name of the device, use the Dns.GetHostName property. A typical default name is "PocketPC".
Example
This example displays the ID and name of the device in messages boxes when the form loads.
To get the device ID, or serial number, you must use platform invoke to access the native Windows CE KernelIoControl function.
Imports System
Imports System.Drawing
Imports System.ComponentModel
Imports System.Diagnostics
Imports System.Windows.Forms
Imports System.Runtime.InteropServices
Imports System.Text
Imports Microsoft.VisualBasic
Public Class DeviceID
Inherits System.Windows.Forms.Form
Declare Function KernelIoControl Lib "CoreDll.dll" _
(ByVal dwIoControlCode As Int32, _
ByVal lpInBuf As IntPtr, _
ByVal nInBufSize As Int32, _
ByVal lpOutBuf() As Byte, _
ByVal nOutBufSize As Int32, _
ByRef lpBytesReturned As Int32) As Boolean
Public Sub New()
Me.Text = "DeviceID"
' Display OK close button.
Me.MinimizeBox = False
End Sub
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
MyBase.Dispose(disposing)
End Sub
Shared Sub Main()
Application.Run(New DeviceID)
End Sub
Private Shared METHOD_BUFFERED As Int32 = 0
Private Shared FILE_ANY_ACCESS As Int32 = 0
Private Shared FILE_DEVICE_HAL As Int32 = &H101
Private Const ERROR_NOT_SUPPORTED As Int32 = &H32
Private Const ERROR_INSUFFICIENT_BUFFER As Int32 = &H7A
Private Shared IOCTL_HAL_GET_DEVICEID As Int32 = _
(&H10000 * FILE_DEVICE_HAL) Or (&H4000 * FILE_ANY_ACCESS) _
Or (&H4 * 21) Or METHOD_BUFFERED
Private Shared Function GetDeviceID() As String
' Initialize the output buffer to the size of a
' Win32 DEVICE_ID structure
Dim outbuff(19) As Byte
Dim dwOutBytes As Int32
Dim done As Boolean = False
Dim nBuffSize As Int32 = outbuff.Length
' Set DEVICEID.dwSize to size of buffer. Some platforms look at
' this field rather than the nOutBufSize param of KernelIoControl
' when determining if the buffer is large enough.
BitConverter.GetBytes(nBuffSize).CopyTo(outbuff, 0)
dwOutBytes = 0
' Loop until the device ID is retrieved or an error occurs.
While Not done
If KernelIoControl(IOCTL_HAL_GET_DEVICEID, IntPtr.Zero, _
0, outbuff, nBuffSize, dwOutBytes) Then
done = True
Else
Dim errnum As Integer = Marshal.GetLastWin32Error()
Select Case errnum
Case ERROR_NOT_SUPPORTED
Throw New NotSupportedException( _
"IOCTL_HAL_GET_DEVICEID is not supported on this device", _
New Win32Exception(errnum))
Case ERROR_INSUFFICIENT_BUFFER
' The buffer is not big enough for the data. The
' required size is in the first 4 bytes of the output
' buffer (DEVICE_ID.dwSize).
nBuffSize = BitConverter.ToInt32(outbuff, 0)
outbuff = New Byte(nBuffSize) {}
' Set DEVICEID.dwSize to size of buffer. Some
' platforms look at this field rather than the
' nOutBufSize param of KernelIoControl when
' determining if the buffer is large enough.
BitConverter.GetBytes(nBuffSize).CopyTo(outbuff, 0)
Case Else
Throw New Win32Exception(errnum, "Unexpected error")
End Select
End If
End While
' Copy the elements of the DEVICE_ID structure.
Dim dwPresetIDOffset As Int32 = BitConverter.ToInt32(outbuff, &H4)
Dim dwPresetIDSize As Int32 = BitConverter.ToInt32(outbuff, &H8)
Dim dwPlatformIDOffset As Int32 = BitConverter.ToInt32(outbuff, &HC)
Dim dwPlatformIDSize As Int32 = BitConverter.ToInt32(outbuff, &H10)
Dim sb As New StringBuilder
Dim i As Integer
For i = dwPresetIDOffset To (dwPresetIDOffset + dwPresetIDSize) - 1
sb.Append(String.Format("{0:X2}", outbuff(i)))
Next i
sb.Append("-")
For i = dwPlatformIDOffset To (dwPlatformIDOffset + dwPlatformIDSize) - 1
sb.Append(String.Format("{0:X2}", outbuff(i)))
Next i
Return sb.ToString()
End Function
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
Try
' Show the device ID.
Dim deviceID As String = GetDeviceID()
MessageBox.Show("Device ID: " + deviceID)
' Show the device name.
Dim deviceName As String = System.Net.Dns.GetHostName()
MessageBox.Show("Device Name: " & deviceName)
Catch ex As Exception
MessageBox.Show(ex.Message.ToString())
End Try
End Sub
End Class
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Diagnostics;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Text;
namespace DeviceID
{
/// <summary>
/// Summary description for DeviceID.
/// </summary>
public class DeviceID : System.Windows.Forms.Form
{
public DeviceID()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();
//
// TODO: Add any constructor code after InitializeComponent call
//
}
/// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
{
base.Dispose( disposing );
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
//
// DeviceID
//
this.Text = "DeviceID";
this.Load += new System.EventHandler(this.DeviceID_Load);
}
static void Main()
{
Application.Run(new DeviceID());
}
#endregion
private static Int32 METHOD_BUFFERED = 0;
private static Int32 FILE_ANY_ACCESS = 0;
private static Int32 FILE_DEVICE_HAL = 0x00000101;
private const Int32 ERROR_NOT_SUPPORTED = 0x32;
private const Int32 ERROR_INSUFFICIENT_BUFFER = 0x7A;
private static Int32 IOCTL_HAL_GET_DEVICEID =
((FILE_DEVICE_HAL) << 16) | ((FILE_ANY_ACCESS) << 14)
| ((21) << 2) | (METHOD_BUFFERED);
[DllImport("coredll.dll", SetLastError=true)]
private static extern bool KernelIoControl(Int32 dwIoControlCode,
IntPtr lpInBuf, Int32 nInBufSize, byte[] lpOutBuf,
Int32 nOutBufSize, ref Int32 lpBytesReturned);
private static string GetDeviceID()
{
// Initialize the output buffer to the size of a
// Win32 DEVICE_ID structure.
byte[] outbuff = new byte[20];
Int32 dwOutBytes;
bool done = false;
Int32 nBuffSize = outbuff.Length;
// Set DEVICEID.dwSize to size of buffer. Some platforms look at
// this field rather than the nOutBufSize param of KernelIoControl
// when determining if the buffer is large enough.
BitConverter.GetBytes(nBuffSize).CopyTo(outbuff, 0);
dwOutBytes = 0;
// Loop until the device ID is retrieved or an error occurs.
while (! done)
{
if (KernelIoControl(IOCTL_HAL_GET_DEVICEID, IntPtr.Zero,
0, outbuff, nBuffSize, ref dwOutBytes))
{
done = true;
}
else
{
int error = Marshal.GetLastWin32Error();
switch (error)
{
case ERROR_NOT_SUPPORTED:
throw new NotSupportedException(
"IOCTL_HAL_GET_DEVICEID is not supported on this device",
new Win32Exception(error));
case ERROR_INSUFFICIENT_BUFFER:
// The buffer is not big enough for the data. The
// required size is in the first 4 bytes of the output
// buffer (DEVICE_ID.dwSize).
nBuffSize = BitConverter.ToInt32(outbuff, 0);
outbuff = new byte[nBuffSize];
// Set DEVICEID.dwSize to size of buffer. Some
// platforms look at this field rather than the
// nOutBufSize param of KernelIoControl when
// determining if the buffer is large enough.
BitConverter.GetBytes(nBuffSize).CopyTo(outbuff, 0);
break;
default:
throw new Win32Exception(error, "Unexpected error");
}
}
}
// Copy the elements of the DEVICE_ID structure.
Int32 dwPresetIDOffset = BitConverter.ToInt32(outbuff, 0x4);
Int32 dwPresetIDSize = BitConverter.ToInt32(outbuff, 0x8);
Int32 dwPlatformIDOffset = BitConverter.ToInt32(outbuff, 0xc);
Int32 dwPlatformIDSize = BitConverter.ToInt32(outbuff, 0x10);
StringBuilder sb = new StringBuilder();
for (int i = dwPresetIDOffset;
i < dwPresetIDOffset + dwPresetIDSize; i++)
{
sb.Append(String.Format("{0:X2}", outbuff[i]));
}
sb.Append("-");
for (int i = dwPlatformIDOffset;
i < dwPlatformIDOffset + dwPlatformIDSize; i ++ )
{
sb.Append( String.Format("{0:X2}", outbuff[i]));
}
return sb.ToString();
}
private void DeviceID_Load(object sender, System.EventArgs e)
{
try
{
// Show the device ID.
string strDeviceID = GetDeviceID();
MessageBox.Show("Device ID: " + strDeviceID);
// Show the device name.
string deviceName = System.Net.Dns.GetHostName();
MessageBox.Show("Device Name: " + deviceName);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message.ToString());
}
}
}
}
Compiling the Code
This example requires references to the following namespaces:
Robust Programming
The following table lists the native KernelIoControl function parameters. All are 32 bits.
Parameter |
Win32 type |
Managed type |
Typical value |
|---|---|---|---|
dwIoControlCode |
DWORD |
IOCTL_HAL_GET_DEVICEID |
|
lpInBuf |
LPVOID |
IntPtr.Zero (no input data required) |
|
nInBufSize |
DWORD |
0 (no input data required) |
|
lpOutBuf |
LPVOID* |
A 20-element Byte array (20 bytes is the size of the DEVICE_ID structure) |
|
nOutBufSize |
DWORD |
20 |
|
lpBytesReturned |
LPWORD |
ref Int32 |
0 |
The lpOutBuf parameter has the following structure:
Structure DEVICE_ID
Private dwSize As Integer
Private dwPresetIDOffset As Integer
Private dwPresetIDBytes As Integer
Private dwPlatformIDOffset As Integer
Private dwPlatformIDBytes As Integer
End Structure
struct DEVICE_ID
{
int dwSize;
int dwPresetIDOffset;
int dwPresetIDBytes;
int dwPlatformIDOffset;
int dwPlatformIDBytes;
}
Return Values and Error Handling
The KernelIoControl function returns true if the device ID was copied to the output buffer; otherwise, it returns false. If KernelIoControl fails, call the managed GetLastWin32Error method to get the Win32 error code. The error code is likely to be either of the following:
ERROR_NOT_SUPPORTED - Indicates that the device does not implement the IOCTL_HAL_GET_DEVICEID control code.
ERROR_INSUFFICIENT_BUFFER - Indicates that the output buffer was not large enough to hold the device ID. The required number of bytes, specified by dwSize in the DEVICE_ID structure, is returned in the first four bytes of the output buffer. If this error occurs, reallocate the output buffer to the size specified by dwSize and call KernelIoControl again.