static extern void DisposeNavEventUPP(NavEventUPP userUPP);
static extern NavStatus NavCreateChooseFileDialog(ref NavDialogCreationOptions options, IntPtr inTypeList,
NavEventUPP inEventProc, NavPreviewUPP inPreviewProc,
NavObjectFilterUPP inFilterProc, ref IntPtr inClientData, out IntPtr navDialogRef);