ValidateRgn info  Overview  Group

The ValidateRgn function validates the client area within a region by removing the region from the current update region of the specified window.

BOOL ValidateRgn(

Parameters

hWnd

Identifies the window whose update region is to be modified.

hRgn

Identifies a region that defines the area to be removed from the update region. If this parameter is NULL, the entire client area is removed.

Return Values

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

The specified region must have been created by a region function. The region coordinates are assumed to be client coordinates.

The BeginPaint function automatically validates the entire client area. Neither the ValidateRect nor ValidateRgn function should be called if a portion of the update region must be validated before the next WM_PAINT message is generated.

See Also

BeginPaint, ExcludeUpdateRgn, InvalidateRect, InvalidateRgn, ValidateRect, WM_PAINT