InvalidateRgn function Null safety user32

int InvalidateRgn (
  1. int hWnd,
  2. int hRgn,
  3. int bErase

The InvalidateRgn function invalidates the client area within the specified region by adding it to the current update region of a window. The invalidated region, along with all other areas in the update region, is marked for painting when the next WM_PAINT message occurs.

BOOL InvalidateRgn(
  HWND hWnd,
  HRGN hRgn,
  BOOL bErase


int InvalidateRgn(int hWnd, int hRgn, int bErase) {
  final _InvalidateRgn = _user32.lookupFunction<
      Int32 Function(IntPtr hWnd, IntPtr hRgn, Int32 bErase),
      int Function(int hWnd, int hRgn, int bErase)>('InvalidateRgn');
  return _InvalidateRgn(hWnd, hRgn, bErase);