Making app only available thing until ended

Is there a way that I can make an app only allow focus on itself and nothing else until it is unloaded? I am making a test program and I don't want the users to be able to store answers in a text file on the hard drive or something and then look at them while writing.

Thanks for help

This keeps your window from losing focus to another window that is already activated but doesn't have focus.

Code:

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Const HWND_TOPMOST = -1
Const HWND_NOTOPMOST = -2
Const SWP_NOSIZE = &H1
Const SWP_NOMOVE = &H2
Const SWP_NOACTIVATE = &H10
Const SWP_SHOWWINDOW = &H40
Private Declare Sub SetWindowPos Lib "User32" (ByVal hWnd As Long, ByVal hWndInsertAfter As Long, _
    ByVal X As Long, ByVal Y As Long, ByVal cx As Long, ByVal cy As Long, ByVal wFlags As Long)

Private Sub FormOnTop()

    SetWindowPos Me.hWnd, HWND_TOPMOST, 0, 0, 0, 0, _
  SWP_NOACTIVATE Or SWP_SHOWWINDOW Or SWP_NOMOVE _
  Or SWP_NOSIZE

End Sub

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