Get the number of children of an outline node.
getOutlineNumChildren([in] LONG outlineHandle, [out, retval] int *n)
A PDF file may contain an outline: a list of bookmarks pointing to chapters, sections, etc. The outline is structured as a tree. For example, the top layer might be a list of chapters, where each chapter contains a list of sections, etc. XpdfViewer uses an opaque handle to represent a node in this tree, i.e., an outline entry. Each node has a title (the string describing the outline entry), a target (location in the document), and possibly a list of child nodes. As a special case, the zero handle indicates the root node, which has a list of children (assuming the PDF file has an outline at all) but no title or target.

This function returns the number of child nodes contained in a specified node. It returns zero if the node has no children.

Pass zero as the outline argument to specify the root node, i.e., to get the number of top-level outline entries.

' start out at the root node scanOutline(0) ... Private Sub scanOutline(outlineHdl As Long) { If outlineHdl <> 0 Then ' do something with this outline entry Else ' this is the root node, which isn't a real entry - it has no title or target End If ' now scan the children of this node (if any) n = viewer.getOutlineNumChildren(outlineHdl) For i = 0 To n-1 scanOutline(viewer.getOutlineChild(outlineHdl, i)) Next i End Sub