AnnotationHelper.GetAnchorInfo Method (AnnotationService, Annotation)


The .NET API Reference documentation has a new home. Visit the .NET API Browser on to see the new experience.

Returns an IAnchorInfo object that provides anchoring information, such as the anchor location, about the specified annotation.

Namespace:   System.Windows.Annotations
Assembly:  PresentationFramework (in PresentationFramework.dll)

public static IAnchorInfo GetAnchorInfo(
	AnnotationService service,
	Annotation annotation


Type: System.Windows.Annotations.AnnotationService

The annotation service to use for this operation.

Type: System.Windows.Annotations.Annotation

The annotation to get anchoring information for.

Return Value

Type: System.Windows.Annotations.IAnchorInfo

An IAnchorInfo object that provides anchoring information about the specified annotation, or null if it cannot be resolved.

GetAnchorInfo is introduced in the Microsoft .NET Framework version 3.5. For more information, see .NET Framework Versions and Dependencies.

Consider a simple document reader application that has a comments pane. The comments pane might be a list box that displays the text from a list of annotations that are anchored to a document. If the user selects an item in the list box, then the application brings into view the paragraph in the document that the corresponding annotation object is anchored to.

The following example demonstrates how to implement the event handler of such a list box that serves as the comments pane.

void annotationsListBox_SelectionChanged(object sender, SelectionChangedEventArgs e)

    Annotation comment = (sender as ListBox).SelectedItem as Annotation;
    if (comment != null)
        // IAnchorInfo info;
        // service is an AnnotationService object
        // comment is an Annotation object
        info = AnnotationHelper.GetAnchorInfo(this.service, comment);
        TextAnchor resolvedAnchor = info.ResolvedAnchor as TextAnchor;
        TextPointer textPointer = (TextPointer)resolvedAnchor.BoundingStart;

.NET Framework
Available since 3.0
Return to top