How do I display PDF bookmarks tab?

Q: What properties do I set so that when I save a newly created PDF
(through merges) the bookmarks automatically are displayed when I open
the PDF?

In other words, I took a bunch of PDFs, merged them, created some
bookmarks, and stamped the document. When a user opens the document I
want the bookmarks to be displayed automatically.
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A:
pdfdoc.GetViewPrefs().SetPageMode(PDFDocViewPrefs.PageMode.e_UseBookmarks);