The labels the document gives its pages, such as i, ii, 1, A-1: a live view over the catalog's PageLabels number tree.
public sealed class PdfPageLabels
ISO 32000-2 §12.4.2 and §7.9.7. The tree maps the index of each range's first page to a page label dictionary; a page takes the range with the greatest key at or below its index. Labels are computed on every call from the tree, which is read through the document's shared number tree reader (Limits-guided lookup, with a checked index of the whole tree as the fallback).
Repairs, each reported the first time it is met (in strict mode, the call throws): pages before the first range (the tree
"shall include a value for page index 0") are numbered in decimal from 1, as Acrobat and PDFBox do (PageLabelsMissingZeroKey);
a value that is not a dictionary, and a negative key, are skipped, so the range before continues (PageLabelInvalid). See
PdfPageLabelRange for the repairs inside a range.
kind:method, kind:property, kind:ctor. Press Esc to clear.RangesGets the ranges, in page order: the entries of the number tree whose key is a page index and whose value is a page label dictionary.RootGets the root of the number tree.GetLabel(Int32)Returns the label of the page at pageIndex.GetLabels()Returns the label of every page, in page order.RemoveRange(Int32)Removes the range starting at startPageIndex: its pages join the range before.SetRange(Int32, PdfPageLabelStyle, String?, Int32)Labels the pages from startPageIndex to the next range: sets or replaces the range starting there.