''' <summary>
''' Parses a PDF document metadata.
''' </summary>
''' <param name="pdfFilename">The filename of PDF document.</param>
Public Shared Sub ParsePdfDocumentMetadata(pdfFilename As String)
    ' open PDF document
    Using pdfDocument As New Vintasoft.Imaging.Pdf.PdfDocument(pdfFilename)
        ' create a memory stream from metadata bytes
        Using mem As New System.IO.MemoryStream(pdfDocument.Metadata)
            ' create XML reader
            Using xmlReader As System.Xml.XmlReader = System.Xml.XmlReader.Create(mem)
                ' parse XML metadata of PDF document

                Dim indentIndex As Integer = 0
                While xmlReader.Read()
                    Select Case xmlReader.NodeType
                        Case System.Xml.XmlNodeType.Element
                            System.Console.WriteLine("{1}<{0}>", xmlReader.Name, GetIndent(indentIndex))
                            indentIndex += 1
                            Exit Select

                        Case System.Xml.XmlNodeType.Text
                            System.Console.WriteLine("{1}  {0}", xmlReader.Value, GetIndent(indentIndex))
                            Exit Select

                        Case System.Xml.XmlNodeType.EndElement
                            indentIndex -= 1
                            System.Console.WriteLine("{1}</{0}>", xmlReader.Name, GetIndent(indentIndex))
                            Exit Select
                    End Select
                End While
            End Using
        End Using
    End Using
End Sub

Private Shared Function GetIndent(indexntIndex As Integer) As String
    Dim indent As New System.Text.StringBuilder()
    For i As Integer = 0 To indexntIndex - 1
        indent.Append("  ")
    Next
    Return indent.ToString()
End Function

/// <summary>
/// Parses a PDF document metadata.
/// </summary>
/// <param name="pdfFilename">The filename of PDF document.</param>
public static void ParsePdfDocumentMetadata(string pdfFilename)
{
    // open PDF document
    using (Vintasoft.Imaging.Pdf.PdfDocument pdfDocument = new Vintasoft.Imaging.Pdf.PdfDocument(pdfFilename))
    {
        // create a memory stream from metadata bytes
        using (System.IO.MemoryStream mem = new System.IO.MemoryStream(pdfDocument.Metadata))
        {
            // create XML reader
            using (System.Xml.XmlReader xmlReader = System.Xml.XmlReader.Create(mem))
            {
                // parse XML metadata of PDF document

                int indentIndex = 0;
                while (xmlReader.Read())
                {
                    switch (xmlReader.NodeType)
                    {
                        case System.Xml.XmlNodeType.Element:
                            System.Console.WriteLine("{1}<{0}>", xmlReader.Name, GetIndent(indentIndex));
                            indentIndex++;
                            break;
                        
                        case System.Xml.XmlNodeType.Text:
                            System.Console.WriteLine("{1}  {0}", xmlReader.Value, GetIndent(indentIndex));
                            break;

                        case System.Xml.XmlNodeType.EndElement:
                            indentIndex--;
                            System.Console.WriteLine("{1}</{0}>", xmlReader.Name, GetIndent(indentIndex));
                            break;
                    }
                }
            }
        }
    }
}

private static string GetIndent(int indexntIndex)
{
    System.Text.StringBuilder indent = new System.Text.StringBuilder();
    for (int i = 0; i < indexntIndex; i++)
        indent.Append("  ");
    return indent.ToString();
}