''' <summary>
''' Saves the revisions of PDF document to the separate files.
''' </summary>
''' <param name="filename">The filename of PDF document.</param>
Public Shared Sub SaveRevisions(filename As String)
    ' open PDF document
    Using document As New Vintasoft.Imaging.Pdf.PdfDocument(filename)
        Dim revisionFilename As String = String.Format("{0}\{1}_rev{{0}}.pdf", System.IO.Path.GetDirectoryName(filename), System.IO.Path.GetFileNameWithoutExtension(filename))

        ' if PDF document has revisions
        If document.Revisions IsNot Nothing Then
            ' for each revision
            For Each revision As Vintasoft.Imaging.Pdf.PdfDocumentRevision In document.Revisions
                ' save revision to a file
                revision.CopyRevisionTo(String.Format(revisionFilename, revision.RevisionNumber))
            Next
        End If
    End Using
End Sub

/// <summary>
/// Saves the revisions of PDF document to the separate files.
/// </summary>
/// <param name="filename">The filename of PDF document.</param>
public static void SaveRevisions(string filename)
{
    // open PDF document
    using (Vintasoft.Imaging.Pdf.PdfDocument document = new Vintasoft.Imaging.Pdf.PdfDocument(filename))
    {
        string revisionFilename = string.Format(@"{0}\{1}_rev{{0}}.pdf",
            System.IO.Path.GetDirectoryName(filename),
            System.IO.Path.GetFileNameWithoutExtension(filename));

        // if PDF document has revisions
        if (document.Revisions != null)
        {
            // for each revision
            foreach (Vintasoft.Imaging.Pdf.PdfDocumentRevision revision in document.Revisions)
                // save revision to a file
                revision.CopyRevisionTo(string.Format(revisionFilename, revision.RevisionNumber));
        }
    }
}