Windows Mobile 6.5
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This function validates the client area within a region by removing the region from the current update region of the specified window.

BOOL WINAPI ValidateRgn(
  HWND hWnd,
  HRGN hRgn


[in] Handle to the window for which you want to modify the update region.


[in] Handle to a region that defines the area that you want to remove from the update region.

Set this parameter to NULL to remove the entire client area.

A nonzero value indicates success.

Zero indicates failure.

You must create the specified region by calling a region function, such as ExtCreateRegion.

ValidateRgn assumes that the region coordinates are client coordinates.

The BeginPaint function validates the entire client area.

Do not call ValidateRect or ValidateRgn if you require validation of a portion of the update region before the next WM_PAINT message is generated.

Windows Embedded CEWindows CE .NET 4.0 and later
Windows MobileWindows Mobile Version 5.0 and later

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