The TOC does not bother for the _style_ of the *page number*. It will
always show what a page field on a given page would show as well. That
said, you would have to use a heading style, make "A, B, ..." the
numbering sequence of it, and tell the page number to include the
chapter number in your appendix sections.
Most of this should be covered in:
See the section on "Numbering, bullets, Headings, Outlines" (by Shauna
OTOH, I would not bother with "folio by chapter", esp. if you only
intend to do it in your appendix. A page number should help your reader
finding stuff as quickly as possible. B-37 is not a very indicator when
leafing through a 500 page book ...
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