Hook for TextBox - VB

Формулировка задачи:

************ форма (имеется TextBox) ************

Private Sub Form_Load()
   Call Hook(Text1.hwnd)
End Sub
 
Private Sub Form_QueryUnload(Cancel As Integer, UnloadMode As Integer)
   Call UnHook(Text1.hwnd)
End Sub

************ модуль ************

Private Declare Function CallWindowProc Lib "user32" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Long, ByVal hwnd As Long, ByVal msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Private Const GWL_WNDPROC As Long = (-4)
Private Const WM_CONTEXTMENU As Long = &H7B
Public defWndProc As Long

Public Sub Hook(hwnd As Long)
   If defWndProc = 0 Then
      defWndProc = SetWindowLong(hwnd, GWL_WNDPROC, AddressOf WindowProc)
   End If
End Sub
 
Public Sub UnHook(hwnd As Long)
   If defWndProc > 0 Then
      Call SetWindowLong(hwnd, GWL_WNDPROC, defWndProc)
      defWndProc = 0
   End If
End Sub
 
Public Function WindowProc(ByVal hwnd As Long, ByVal uMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
   Select Case uMsg
      Case WM_CONTEXTMENU
        'выполняется во время хука
        'ничего не делаем
         WindowProc = 1
      Case Else
         WindowProc = CallWindowProc(defWndProc, hwnd, uMsg, wParam, lParam)
   End Select
End Function

Вопрос

Почему в Win7 (x64) данный код работает(ПКМ не обрабатывается при Text1_MouseUp), а в WinXP(x86) не работает?

Решение задачи: «Hook for TextBox»

textual
                            Листинг программы 
                        

                            If Win64 Then
 Private Declare PtrSafe Function CallWindowProc Lib "user32" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As LongPtr, ByVal hWnd As LongPtr, ByVal Msg As Long, ByVal wParam As LongPtr, ByVal lParam As LongPtr) As LongPtr
 Private Declare PtrSafe Function FreeLibrary Lib "kernel32" (ByVal hLibModule As LongPtr) As Long
 Private Declare PtrSafe Function GetProcAddress Lib "kernel32" (ByVal hModule As LongPtr, ByVal lpProcName As String) As LongPtr
 Private Declare PtrSafe Function LoadLibrary Lib "kernel32" Alias "LoadLibraryA" (ByVal lpLibFileName As String) As LongPtr
 Private Declare PtrSafe Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (ByVal pDest As Any, pSrc As Any, ByVal ByteLen As LongPtr)
 
 Private Declare PtrSafe Function GlobalAlloc Lib "kernel32" (ByVal wFlags As Long, ByVal dwBytes As LongPtr) As LongPtr
 Private Declare PtrSafe Function GlobalFree Lib "kernel32" (ByVal hMem As LongPtr) As LongPtr
#Else
 Private Declare Function CallWindowProc Lib "user32.dll" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Long, ByVal hwnd As Long, ByVal msg As Long, ByVal wParam  As Long, ByVal lParam As Long) As Long
 Private Declare Function FreeLibrary Lib "kernel32.dll" (ByVal hLibModule As Long) As Long
 Private Declare Function GetProcAddress Lib "kernel32.dll" (ByVal hModule As Long, ByVal lpProcName As String) As Long
 Private Declare Function LoadLibrary Lib "kernel32.dll" Alias "LoadLibraryA" (ByVal lpLibFileName As String) As Long
 Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (ByVal pDest As Any, pSrc As Any, ByVal ByteLen As Long)
 
 Private Declare Function GlobalAlloc Lib "kernel32.dll" (ByVal wFlags As Long, ByVal dwBytes As Long) As Long
 Private Declare Function GlobalFree Lib "kernel32.dll" (ByVal hMem As Long) As Long
#End If
                        