I want my application to be always running. I have included password so that if someone tries to close the application, it will ask for password. Now I am trying to prevent windows from shutting down, restart or logging off while my application is running. Whenever it happens, my application will flash some message. I tried MsgHook component (MsgHoo32.OCX) from http://vb.mvps.org/tools/MsgHook/ to intercept windows message WM_QUERYENDSESSION
I have 2 problems.
1. In the WM_QUERYENDSESSION description it is mentioned that the application may return FALSE to cancel shutdown. How can I return a value while using MsgHook.
2. I used following code without returning any value. It works, but some other programs (mostly in system tray) are still unloaded. After that my program shows "Shutting Down" message & then shut down is cancelled.
How can I prevent shutdown so that no program should be closed?
Thanks
I have 2 problems.
1. In the WM_QUERYENDSESSION description it is mentioned that the application may return FALSE to cancel shutdown. How can I return a value while using MsgHook.
2. I used following code without returning any value. It works, but some other programs (mostly in system tray) are still unloaded. After that my program shows "Shutting Down" message & then shut down is cancelled.
Code:
Private Const WM_QUERYENDSESSION = &H11
Private Const ENDSESSION_LOGOFF As Long = &H80000000
Private Const WM_CANCELMODE = &H1F
Private Sub Form_Load()
Msghook1.HwndHook = Me.hWnd 'intercept messages for my window
Msghook1.Message(WM_QUERYENDSESSION) = True 'enable event for WM_QUERYENDSESSION
End Sub
Private Sub Msghook1_Message(ByVal msg As Long, ByVal wp As Long, ByVal lp As Long, result As Long)
If msg = WM_QUERYENDSESSION Then
' result = False
MsgBox "Shutting Down"
' Else
' result = Msghook1.InvokeWindowProc(msg, wp, lp)
End If
End Sub
Private Sub Form_QueryUnload(Cancel As Integer, UnloadMode As Integer)
Msghook1.Message(WM_QUERYENDSESSION) = False
Msghook1.HwndHook = 0 'unhook any window
End SubHow can I prevent shutdown so that no program should be closed?
Thanks