Retrieves the size of the content area for the background defined by the visual style
#include <WinAPITheme.au3>
_WinAPI_GetThemeBackgroundContentRect ( $hTheme, $iPartID, $iStateID, $hDC, $tRECT )
| $hTheme | Handle to a window's specified theme data. |
| $iPartID | The part that contains the content area. |
| $iStateID | The state of the part. |
| $hDC | Handle to the device context to use when drawing. |
| $tRECT | $tagRECT structure that contains the total background rectangle. This is the area inside the borders or margins. |
| Success: | $tagRECT structure that contains the content area background rectangle. |
| Failure: | Sets the @error flag to non-zero, @extended flag may contain the HRESULT error code. |
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