static extern int OleDraw([MarshalAs(UnmanagedType.IUnknown)] object pUnk,

       public static extern int OleDraw(IntPtr pUnk, int dwAspect, IntPtr hdcDraw, ref Rectangle lprcBounds);

       /// Creates a bitmap from the supplied ActiveX control using OleDraw

           OleDraw(pUnk, 1, hdc, ref rect);