Microsoft KB Archive/249144

Knowledge Base

How To Identify the CE Device Connected to the Desktop Machine

Article ID: 249144

Article Last Modified on 7/1/2004

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APPLIES TO

• Microsoft Visual Basic 5.0 Professional Edition
• Microsoft Visual Basic 6.0 Professional Edition
• Microsoft Visual Basic 5.0 Enterprise Edition
• Microsoft Visual Basic 6.0 Enterprise Edition
• Microsoft Windows CE 2.0 for the Handheld PC
• Microsoft Windows CE 2.11 for the Handheld PC
• Microsoft Windows CE 2.12 for the Handheld PC
• Microsoft Windows CE 3.0 for the Handheld PC

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This article was previously published under Q249144

SUMMARY

This article demonstrates how to call the RAPI functions in Visual Basic to retrieve the identification information from the registry on the remote Windows CE device connected to the desktop. The application will run on the desktop and requires that the desktop machine communicate with the Windows CE device using either Windows CE Services version 2.x or ActiveSync version 3.x.

MORE INFORMATION

1. Start a new Standard EXE in Visual Basic. Form1 is created by default.
2. Add a CommandButton (Command1) to Form1.

3. Paste the following into the code module of Form1:

   Option Explicit
   
   Private Sub Form_Load()
       Command1.Caption = "Get connected device name"
   End Sub
   
   Private Sub Command1_Click()
       Dim lret As Long
       Dim lcon As Long
       
       ' Initialize RAPI
       lcon = ConnectRapi
       If lcon <> ERROR_SUCCESS Then
          MsgBox "Failure to initialize RAPI"
       Else
          MsgBox "RAPI was initialized successfully"
       End If
       
       ' Retrieve the registry information on the remote device
       lret = ReadCEREgistry
       
       ' Uninitialize RAPI
       lcon = DisconnectRapi
       If lcon <> ERROR_SUCCESS Then
          MsgBox "Failure to uninitialize RAPI"
       Else
          MsgBox "RAPI was uninitialized successfully"
       End If
          
   End Sub
                       

4. From the Project menu, choose Add Module. Module1 will be added to the project.

5. Paste the following code into Module1:

   Public Const HKEY_CLASSES_ROOT = &H80000000
   Public Const HKEY_CURRENT_USER = &H80000001
   Public Const HKEY_LOCAL_MACHINE = &H80000002
   Public Const ERROR_SUCCESS = 0
   Public Const REG_DWORD = 4        '32-bit number.
   Public Const REG_SZ = 1
   
   Type RAPIINIT
       cbsize As Long
       heRapiInit As Long
       hrRapiInit As Long
   End Type
   
   Declare Function CeRapiUninit Lib "rapi.dll" () As Long
   
   Declare Function CeRapiInitEx Lib "rapi.dll" ( _
       pRapiInit As RAPIINIT) As Long
       
   Declare Function CeRegOpenKeyEx Lib "rapi.dll" ( _
       ByVal hkey As Long, _
       ByVal lpSubKey As Long, _
       ByVal ulOptions As Long, _
       ByVal samDesired As Long, _
       phkResult As Long) As Long
       
   Declare Function CeRegQueryValueEx Lib "rapi.dll" ( _
       ByVal hkey As Long, _
       ByVal lpValueName As Long, _
       ByVal lpReserved As Long, _
       lpType As Long, _
       ByVal lpdata As Long, _
       lpcbData As Long) As Long
       
   Declare Function CeRegQueryValueExLong Lib "rapi.dll" _
       Alias "CeRegQueryValueEx" ( _
       ByVal hkey As Long, _
       ByVal lpValueName As Long, _
       ByVal lpReserved As Long, _
       lpType As Long, _
       lpdata As Long, _
       lpcbData As Long) As Long
       
   Declare Function CeRegQueryValueExString Lib "rapi.dll" _
       Alias "CeRegQueryValueEx" ( _
       ByVal hkey As Long, _
       ByVal lpValueName As Long, _
       ByVal lpReserved As Long, _
       lpType As Long, _
       ByVal lpdata As Long, _
       lpcbData As Long) As Long
   
   Declare Function CeRegCloseKey Lib "rapi.dll" ( _
       ByVal hkey As Long) As Long
   
   ' Initialize RAPI
   Function ConnectRapi() As Long
       Dim lcon As Long
       Dim lRapiInit As RAPIINIT
       
       With lRapiInit
           .cbsize = Len(lRapiInit)
           .heRapiInit = 0
           .hrRapiInit = 0
       End With
       
       lcon = CeRapiInitEx(lRapiInit)
       ConnectRapi = lcon
   End Function
   
   ' Uninitialize RAPI
   Function DisconnectRapi() As Long
       Dim lcon As Long
       lcon = CeRapiUninit
       DisconnectRapi = lcon
   End Function
   
   ' Read the registry on the CE device
   Function ReadCEREgistry() As Long
       Dim lret As Long
       Dim phkResult As Long
       Dim lpType As Long
       Dim lpdata As String
       Dim lpvalue As Long
       Dim lpcbData As Long
       Dim data As String
       Dim key As String
       Dim lpdwdisposition As Long
       Dim value As String
       
       key = "Ident"
       lret = CeRegOpenKeyEx(HKEY_LOCAL_MACHINE, StrPtr(key), _
                             0, 0, phkResult)
       
       If lret <> ERROR_SUCCESS Then
           MsgBox "Failure to open key.  Error: " & lret
       Else
           value = "Name"
           lret = CeRegQueryValueEx(phkResult, StrPtr(value), _
                                    0, lpType, 0, lpcbData)
           Select Case lpType
               ' -- For strings
               Case REG_SZ:
                   ' Allocate string space
                   lpdata = String(lpcbData, 0)
                   
                   ' Query the string value
                   lret = CeRegQueryValueExString(phkResult, StrPtr(value), _
                             CLng(0), lpType, StrPtr(lpdata), lpcbData)
                             
                   If lret = ERROR_SUCCESS Then
                       MsgBox "The name of the currently connected " & _
                               "device is " & Left(lpdata, lpcbData - 1)
                   Else
                       MsgBox "Your device does not have a name"
                       lpdata = ""
                   End If
                   
               '-- For DWORDS
               Case REG_DWORD:
                   lret = CeRegQueryValueExLong(phkResult, StrPtr(value), _
                           CLng(0), lpType, lpvalue, lpcbData)
                   If lret = ERROR_SUCCESS Then MsgBox lpvalue
                   
               ' -- All other data types not supported
               Case Else
                   lret = -1
           End Select
       End If
       
       ReadCEREgistry = lret
   End Function
                       

6. Press F5 to run the application.
7. Click Command1 and you should get 3 messages showing the status of RAPI initialization, the device's name, and the status of RAPI uninitialization.

Additional query words: RAPI wce vbce vbce6 eVB

Keywords: kbhowto kbapi kbtoolkit KB249144

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