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Manipulating Annotations

This article outlines the most commonly used manipulations with regard to Annotations.

The types of manipulations that can be performed on annotations include:

  • Presentation in the document;

  • Retrieving annotations;

  • Inserting an annotation;

  • Deleting an annotation;

  • Splitting an annotation at a given position.


By default, all annotations are markup-only in the sense that they do not have any appearance. If you want to display a highlight, range brackets or anything else, you can use the UI layers feature of RadRichTextEditor. You can read more about them in this article.

Methods for Retrieving Annotations

  • RadDocument exposes the following general methods for retrieving annotation markers or checking if such exist in the document at all:
bool containsBookamrks = this.radRichTextEditor1.Document.ContainsAnnotationMarkersOfType<BookmarkRangeStart>();
IEnumerable<BookmarkRangeStart> markers = this.radRichTextEditor1.Document.GetAnnotationMarkersOfType<BookmarkRangeStart>();

Dim containsBookamrks As Boolean = Me.radRichTextEditor1.Document.ContainsAnnotationMarkersOfType(Of BookmarkRangeStart)()
Dim markers As IEnumerable(Of BookmarkRangeStart) = Me.radRichTextEditor1.Document.GetAnnotationMarkersOfType(Of BookmarkRangeStart)()

  • Methods for retrieving the containing annotations around a particular inline. This is particularly convenient if you would like to perform checks against the position where the caret is at. First, you can obtain the current inline like this:
Inline currentInline = this.radRichTextEditor1.Document.CaretPosition.GetCurrentInline();

Dim currentInline As Inline = Me.radRichTextEditor1.Document.CaretPosition.GetCurrentInline()

and then, check if this inline is contained in a range using one of the methods below:

bool isInRange = this.radRichTextEditor1.Document.IsInAnnotationRange<BookmarkRangeStart>(inline);
IEnumerable<BookmarkRangeStart> ranges = this.radRichTextEditor1.Document.GetContainingAnnotationRanges<BookmarkRangeStart>(inline);

Dim isInRange As Boolean = Me.radRichTextEditor1.Document.IsInAnnotationRange(Of BookmarkRangeStart)(inline)
Dim ranges As IEnumerable(Of BookmarkRangeStart) = Me.radRichTextEditor1.Document.GetContainingAnnotationRanges(Of BookmarkRangeStart)(inline)


  • More finely tuned methods that filter the annotation ranges at the time of their retrieval include:

{{source=..\SamplesCS\RichTextEditor\DocumentElements\ManipulatingAnnotations.cs region=inRange1}} {{source=..\SamplesVB\RichTextEditor\DocumentElements\ManipulatingAnnotations.vb region=inRange1}}

bool isInRange1 = this.radRichTextEditor1.Document.IsInAnnotationRange<BookmarkRangeStart>(inline, Filter, true);
IEnumerable<BookmarkRangeStart> ranges1 = this.radRichTextEditor1.Document.GetContainingAnnotationRanges<BookmarkRangeStart>(inline, Filter, true);

Dim isInRange1 As Boolean = Me.radRichTextEditor1.Document.IsInAnnotationRange(Of BookmarkRangeStart)(inline, AddressOf Filter, True)
Dim ranges1 As IEnumerable(Of BookmarkRangeStart) = Me.radRichTextEditor1.Document.GetContainingAnnotationRanges(Of BookmarkRangeStart)(inline, AddressOf Filter, True)

Inserting Annotations

Annotations can be inserted in the document using the following method of RadDocumentEditor.

documentEditor.InsertAnnotationRange(new BookmarkRangeStart(), new BookmarkRangeEnd());

documentEditor.InsertAnnotationRange(New BookmarkRangeStart(), New BookmarkRangeEnd())

There are also some methods that insert specific types of annotations for the commonly used types, such as Hyperlinks, Comments, etc. For more information, check the respective article.

Deleting Annotations

In order to delete an annotation, you need to obtain a reference to its range start first. After that, you can use the following method of RadDocumentEditor to remove it.



Note that this method will remove the annotation, but will keep its contents. In order to delete the contents as well, you can select it and use the Delete method of the editor:



There are also some methods that remove specific types of annotations for the commonly used types, such as Hyperlinks, Comments, etc. For more information, check the respective article.

Splitting Annotations

Some user scenarios require that there would be an easy way to split annotation ranges. In such cases, one can use the following methods:

documentEditor.SplitAnnotationRange(start, documentPosition);

documentEditor.SplitAnnotationRange(start, documentPosition)

See Also

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