' 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)()
' Distance annotation
Dim distanceAnnotation As New AnnotationInfo() With { _
.AnnotationPosition = New Point(852.0, 287.0), _
.Box = New Rectangle(248.0F, 287.0F, 115.0F, 25.0F), _
.PageNumber = 0, _
.PenColor = 1201033, _
.PenStyle = 0, _
.PenWidth = 1, _
.SvgPath = "M248.73201877934272,295.5439436619718 l115.28309859154929,-4.192112676056338", _
.Text = vbCr & vbLf & "Anonym A.: 115px", _
.Type = AnnotationType.Distance, _
.CreatorName = "Anonym A." _
}
' Add annotation to list
annotations.Add(distanceAnnotation)
' Export annotation and save output file
CommonUtilities.SaveOutputDocument(inputFile, annotations, DocumentType.Pdf)
Catch exp As Exception
Console.WriteLine(exp.Message)
End Try