**I am using the following code,**
    var db=session.getCurrentDatabase()
    var nc:NotesNoteCollection=db.createNoteCollection(true);
    nc.selectAllDesignElements(true);
    nc.buildCollection()
    var filename = "d:\\dxl\\xpDXL.dxl";
    var stream:NotesStream=session.createStream()
    if (stream.open(filename)) {
            stream.truncate(); // Any existing file is erased
            var exporter:NotesDxlExporter = session.createDxlExporter();
            stream.writeText(exporter.exportDxl(db))
    }
** 它不导出设计元素。但在 DXL 中,它有文档集合。**