Check if an annotation has changed in UWP

There are several events you can subscribe to in order to be informed of changes to annotations:

AnnotationsCreated
AnnotationsDeleted
AnnotationsUpdated
OnAnnotationPresetUpdate
OnAnnotationSelectionChanged
OnAnnotationPressed
IsEditableAnnotation
OnAnnotationsWillChange

Here’s how you can add a handler to be informed of deleted annotations:

{
    // After the PDF has been loaded.
    pdfView.Document.AnnotationsDeleted += OnAnnotationsDeleted;
}

private void OnAnnotationsDeleted(object sender, IList<IAnnotation> annotations)
{
    foreach (var annotation in annotations)
    {
        Debug.WriteLine($"OnAnnotationsDeleted: {annotation.Id}");
    }
}

You can find other examples and read more about events in our events guide.