### IDirectDrawSurface3::EnumOverlayZOrders

The IDirectDrawSurface3::EnumOverlayZOrders method enumerates the overlay surfaces on the specified destination. The overlays can be enumerated in front-to-back or back-to-front order.

HRESULT EnumOverlayZOrders(

DWORD dwFlags,

LPVOID lpContext,

LPDDENUMSURFACESCALLBACK lpfnCallback

);

##### Parameters

dwFlags
  One of the following flags:

  DDENUMOVERLAYZ_BACKTOFRONT
  | Enumerates overlays back to front.
  DDENUMOVERLAYZ_FRONTTOBACK
  | Enumerates overlays front to back.

lpContext
  Address of the user-defined context that will be passed to the callback function for each overlay surface.
lpfnCallback
  Address of the EnumSurfacesCallback callback function that will be called for each surface being overlaid on this surface.

##### Return Values

If the method succeeds, the return value is DD_OK.

If the method fails, the return value may be one of the following error values:

DDERR_INVALIDOBJECT
DDERR_INVALIDPARAMS