The GetStructTreeRoot method returns an object representing the root node of the structure tree. This node is not visible from viewer applications; it only serves as a starting point for creation of the structure tree. Whenever a PDF file is loaded, if it contains Marked Content elements that are not referenced in the structure tree, they will be added automatically to the root node.
IStructElement GetStructTreeRoot()
TObject instance representing the root node of the structure tree in the current document.
A Structure Tree node will not be visible in viewer applications unless the node contains at least one user property and a non-empty textual name is assigned to it. See AddUserProperty method and Name property in IStructElement interface for details.
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