Imports PdfSharp.Pdf
Imports PdfSharp.Pdf.Annotations
Imports PdfSharp.Pdf.IO
Imports PdfSharp.Drawing
Public Class frmAnnotations
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Try
            Dim doc As PdfDocument = PdfReader.Open(CURRENT_DOC_PATH, PdfDocumentOpenMode.Modify)
            Dim firstPage As PdfPage = doc.Pages(txtSeitenzahl.Text)

            Dim gfx As XGraphics = XGraphics.FromPdfPage(firstPage)
            Dim rect As XRect = gfx.Transformer.WorldToDefaultPage(New XRect(New XPoint(30, 60), New XSize(30, 30)))

            Dim annot As PdfTextAnnotation = New PdfTextAnnotation


            annot.Title = txttitle.Text
            'annot.Subject = txtsubject.Text
            annot.Contents = txtcontent.Text
            annot.Rectangle = New PdfRectangle(rect)


            firstPage.Annotations.Add(annot)
            doc.Save(CURRENT_DOC_PATH)
            Me.Close()
        Catch ex As Exception
            MsgBox(ex.Message, MsgBoxStyle.Critical)
        End Try


    End Sub
End Class