InvalidateRgn function 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
);

Implementation

int InvalidateRgn(int hWnd, int hRgn, int bErase) =>
    _InvalidateRgn(hWnd, hRgn, bErase);