' For complete examples and data files, please go to https://github.com/groupdocsannotation/GroupDocs_Annotation_NET
Try
' Get input file stream
Dim inputFile As Stream = New FileStream(CommonUtilities.MapSourceFilePath(filePath), FileMode.Open, FileAccess.ReadWrite)
' Initialize list of AnnotationInfo
Dim annotations As New List(Of AnnotationInfo)()
' Resource redaction annotation
Dim resourceRedactionAnnotation As New AnnotationInfo() With { _
.AnnotationPosition = New Point(852.0, 271.78), _
.BackgroundColor = 3355443, _
.Box = New Rectangle(466.0F, 271.0F, 69.0F, 62.0F), _
.PageNumber = 0, _
.PenColor = 3355443, _
.Type = AnnotationType.ResourcesRedaction, _
.CreatorName = "Anonym A." _
}
' Add annotation to list
annotations.Add(resourceRedactionAnnotation)
' Export annotation and save output file
CommonUtilities.SaveOutputDocument(inputFile, annotations, DocumentType.Pdf)
Catch exp As Exception
Console.WriteLine(exp.Message)
End Try