فرآیند پیام ارسال شده به پنجره WindowProc

Subclassing Controls

WindowProc callback function

Declare PtrSafe Function CallWindowProcA Lib "user32" (ByVal lpPrevWndFunc As LongPtr, ByVal hwnd As LongPtr, ByVal Msg As Long, ByVal wParam As LongPtr, ByVal lParam As LongPtr) As Long

Declare PtrSafe Function SetWindowLongPtrA Lib "user32" (ByVal hwnd As LongPtr, ByVal nIndex As Long,ByVal dwNewLong As LongPtr) As Long

(Public Const GWL_WNDPROC = (-4

Global oldwndproc As LongPtr

Global wndHW As LongPtr

: Form_Load

wndHw=Me.Hwnd

(oldwndproc = SetWindowLongPtrA(Me.hwnd, GWL_WNDPROC, AddressOf WndProc

: Form_Unload

SetWindowLongPtrA wndHw, GWL_WNDPROC, oldwndproc

Public Function WndProc(ByVal lhwnd As LongPtr, ByVal uMsg As Long, ByVal wParam As LongPtr, ByVal lParam As LongPtr) As Long

If uMsg = 516 Then 'WM_RBUTTONDOWNU           

        'Debug.Print "Intercepted WM_CONTEXTMENU at " & Now                        

       " MsgBox "Mouse Right Button Was Clicked                       

          WndProc=-1                      

ElseIf uMsg = WM_KEYDOWN Then        

           MsgBox wParam                    

             WndProc = True                    

     Else ' Send all other messages to the default message handler     

        (WndProc = CallWindowProcA(oldwndproc, lhwnd, uMsg, wParam, lParam

     End If

End Function

Public Const WM_KEYDOWN = &H100

Public Const WM_KEYUP = &H101

Public Const WM_CHAR = &H102

Public Const VK_RETURN = &HD

Public Const VK_UP = &H26

Public Const VK_DOWN = &H28

Public Const VK_HOME = &H24

Public Const VK_LEFT = &H25

Public Const VK_PRIOR = &H21

Public Const VK_LBUTTON = &H1  ' Left mouse button

Public Const VK_RBUTTON = &H2  ' Right mouse button

Public Const VK_MBUTTON = &H4  ' Middle mouse button (three-button mouse)

Public Const SC_SIZE = &HF000&

Public Const SC_MOVE = &HF010&

Public Const SC_MINIMIZE = &HF020&

Public Const SC_MAXIMIZE = &HF030&

Public Const SC_NEXTWINDOW = &HF040&

Public Const SC_PREVWINDOW = &HF050&

Public Const SC_CLOSE = &HF060&

Const WM_NCLBUTTONDOWN As Integer = 161
        Const WM_SYSCOMMAND As Integer = 274
        Const HTCAPTION As Integer = 2
        Const SC_MOVE As Integer = 61456

        If (Msg = WM_SYSCOMMAND) And (WParam = SC_MOVE) Then
            Return
        End If

        If (Msg = WM_NCLBUTTONDOWN) And (WParam = HTCAPTION) Then
            Return
        If (Msg = WM_RBUTTONDOWN) And (WParam = WM_RBUTTONDOWN) Then
            Return
        End If

    

وقتی دابل کلیک روی قسمت تایتل بار انجام میشود یا بعبارتی  قسمت کپشن پنجره عمل ماکسیمایز پنجره انجام خواهد گرفت

If umsg = WM_NCLBUTTONDBLCLK And wParam = 2 Then Exit Function

SYsMenu عمل نکردن منوهای تایتل بار یا 

If umsg = WM_SYSCOMMAND And ((wParam = SC_CLOSE) Or (wParam = SC_MINIMIZE) Or (wParam = SC_MAXIMIZE)) Then

Exit Function

مثال دیگر :

    wm-ncdestroy   &H82

If Msg = WM_NCDESTROY Then 

SetWindowLong hWnd,GWL_WNDPROC,OldWindowProc

End If 

wm-contextmenu  &H7B

If Msg <> WM_CONTEXTMENU Then

NoPopupWindowProc = CallWindowProc(OldWindowProc,hWnd

,Msg,wParam,lParam)

----------------------------------------

 اگر از HOOK  استفاده شود و آیدی WH_MOUSE یا WH_MOUSE_LL

If Wparam=WM_NCLBUTTONDBLCLK Then 

     MouseHookProc=NoneZero

End If

WM_RBUTTONDOWN   wm-rbuttondown   &H204

(20×16)×1.6+4=516 ( DECIMAL )

516÷16=32  

516-(32×16)=4

(516÷16)×10=320

320÷16=20

List Of Windows Message  SendMessageList