Private Declare Function IsIconic Lib "user32" (ByVal hwnd As Long) As Long
te devuelve si esta minimizada
Private Declare Function IsWindow Lib "user32" (ByVal hwnd As Long) As Long
te dice si es ventana en realidad el handle
Private Declare Function IsZoomed Lib "user32" (ByVal hwnd As Long) As Long
te dice si esta maximizada
Private Declare Function IsWindowEnabled Lib "user32" (ByVal hwnd As Long) As Long
te dice si esta habilitada la ventana (puede recibir input del mouse teclado, etc, )
Private Declare Function IsWindowVisible Lib "user32" (ByVal hwnd As Long) As Long
si esta visible o no la ventana
tomado de
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