Retrieves the styles of a GUI window.
GUIGetStyle ( [winhandle] )
| winhandle | [optional] Windows handle as returned by GUICreate() (default is the previously used window). | 
| Success: | a two-element array that containing the styles information: $aArray[0] = Style $aArray[1] = ExStyle | 
| Failure: | sets the @error flag to non-zero. | 
Be careful Style changes after GUISetState().
#include <GUIConstantsEx.au3>
#include <WindowsStylesConstants.au3>
Example()
Func Example()
    Local $hGUI = GUICreate("Gui Style", 260, 100)
    Local $idBtn_Style = GUICtrlCreateButton("Set Style", 45, 50, 150, 20)
    Local $aGUIStyle = GUIGetStyle($hGUI) ; be careful the style change after opening
    GUISetState(@SW_SHOW)
    Local $bNewStyle = False, $idMsg
    While 1
        $idMsg = GUIGetMsg()
        Switch $idMsg
            Case $GUI_EVENT_CLOSE
                ExitLoop
            Case $idBtn_Style
                If Not $bNewStyle Then
                    GUISetStyle(BitOR($WS_POPUPWINDOW, $WS_THICKFRAME), BitOR($WS_EX_CLIENTEDGE, $WS_EX_TOOLWINDOW))
                    GUICtrlSetData($idBtn_Style, 'Undo Style')
                    $bNewStyle = True
                Else
                    GUISetStyle($aGUIStyle[0], $aGUIStyle[1])
                    GUICtrlSetData($idBtn_Style, 'Set Style')
                    $bNewStyle = False
                EndIf
            Case Else
        EndSwitch
    WEnd
    GUIDelete($hGUI)
EndFunc   ;==>Example