Private Sub Button_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)

    Dim wb As New WriteableBitmap(chart, Nothing)

    Dim doc As New C1PdfDocument()

    doc.Compression = CompressionLevelEnum.BestSpeed

    doc.DrawImage(wb, New Rect(New Point(), doc.PageSize), ContentAlignment.TopLeft, Stretch.None)

    Dim sfd As New SaveFileDialog()

    If sfd.ShowDialog() = True Then

        Using stream = sfd.OpenFile()

            doc.Save(stream)

        End Using

    End If

End Sub

private void Button_Click(object sender, RoutedEventArgs e)

{

   WriteableBitmap wb = new WriteableBitmap(chart, null);

   C1PdfDocument doc = new C1PdfDocument();

   doc.Compression = CompressionLevelEnum.BestSpeed;

   doc.DrawImage(wb, new Rect(new Point(),doc.PageSize), ContentAlignment.TopLeft, Stretch.None);

   SaveFileDialog sfd = new SaveFileDialog()

   {

      DefaultExt = "pdf",

      Filter = "Pdf files (*.pdf)|*.pdf",

   };

   if (sfd.ShowDialog() == true)

   {

     using (var stream = sfd.OpenFile())

     {

        doc.Save(stream);

     }

   }

}