StructureTree

Updated on Feb 19, 2026

Minimum Version	Q3 2025
Related Feature:	Accessibility Support

The StructureTree class represents the root of the structure elements tree of the RadFixedDocument. It offers a public ChildElements collection property allowing to add different StructureElements.

StructureElement

The class represents a structure element in the document. The available public properties that can be set are listed in the table:

Property	Description
ID	Gets or sets the unique identifier for the entity.
ActualText	Gets or sets the actual text of the structure element.
AlternateDescription	Gets or sets the alternate description of the structure element.
Language	Gets or sets the language of the structure element.
StandardStructureType	Gets the type of the structure element.
CustomStructureType	Gets the custom type of the structure element.
TaggedElements	Gets a read-only collection of structural elements that have been tagged with this structure element.
Parent	Gets or sets the parent structure tree of the structure element.

Structure Tag Types

A set of standard structure types define the meaning of structure elements, such as paragraphs, headings, articles, and tables. The available options are:

Structure Tag Type	Description
None	No specific structure tag type.
Document	A complete document. This is the root element of any structure tree containing multiple parts or multiple articles.
Part	A large-scale division of a document. This type of element is appropriate for grouping articles or sections.
Article	A relatively self-contained body of text constituting a single narrative or exposition. Articles should be disjoint; that is, they should not contain other articles as constituent elements.
Section	A container for grouping related content elements. For example, a section might contain a heading, several introductory paragraphs, and two or more other sections nested within it as subsections.
Division	A generic block-level element or group of elements.
BlockQuote	A portion of text consisting of one or more paragraphs attributed to someone other than the author of the surrounding text.
Caption	A brief portion of text describing a table or figure.
TableOfContent	An individual member of a table of contents.
Index	A sequence of entries containing identifying text accompanied by reference elements that point out occurrences of the specified text in the main body of a document.
NonStruct	A grouping element having no inherent structural significance; it serves solely for grouping purposes. This type of element differs from a division in that it is not interpreted or exported to other document formats; however, its descendants are to be processed normally.
Private	A grouping element containing private content belonging to the application producing it. The structural significance of this type of element is unspecified and is determined entirely by the producer application. Neither the Private element nor any of its descendants are to be interpreted or exported to other document formats.
Paragraph	Represents a paragraph element.
Heading	Represents a heading element.
HeadingLevel1	Represents a level 1 heading.
HeadingLevel2	Represents a level 2 heading.
HeadingLevel3	Represents a level 3 heading.
HeadingLevel4	Represents a level 4 heading.
HeadingLevel5	Represents a level 5 heading.
HeadingLevel6	Represents a level 6 heading.
List	Represents a list element.
ListItem	Represents a list item element.
ListLabel	Represents a list label element.
ListBody	Represents a list body element.
Table	Represents a table element.
TableRow	Represents a table row element.
TableHeader	Represents a table header element.
TableData	Represents a table data element.
TableHead	Represents a table head element.
TableBody	Represents a table body element.
TableFooter	Represents a table footer element.
Span	Represents a span element.
Quotation	Represents a quotation element.
Note	Represents a note element.
Reference	Represents a reference element.
BibEntry	Represents a bibliographic entry element.
Code	Represents a code element.
Link	Represents a link element.
Annotation	Represents an annotation element.
Ruby	Represents a ruby element.
RubyBaseText	Represents the base text of a ruby element.
RubyAnnotationText	Represents the annotation text of a ruby element.
RubyPunctuation	Represents the punctuation of a ruby element.
Warichu	Represents a warichu element.
WarichuText	Represents the text of a warichu element.
WarichuPunctuation	Represents the punctuation of a warichu element.
Figure	Represents a figure element.
Formula	Represents a formula element.
Form	Represents a form element.

See Also

• RadFixedDocument
• Tagged PDF
• Marked Content
• Accessibility Support