Public Declare Function GetTopWindow Lib "user32" (ByVal hWnd As Long) As Long

For Click Event of form write this code:
Private Sub Form_Click()
Dim n As Long
n = GetTopWindow(0) 'or n=GetToWindow(GetDesktopWindow())
if n<>me.hwnd then
msgbox "!="
else
msgbox "="
end if
End Sub

while when i click on form n<>me.hwnd?