public static void GetInfoAboutPDF(string filename)
{
    // open PDF document
    using (Vintasoft.Imaging.Pdf.PdfDocument document = 
        new Vintasoft.Imaging.Pdf.PdfDocument(filename))
    {
        // show information about PDF document
        if (document.IsEncrypted)
            System.Console.WriteLine(string.Format("Encryption  : {0}", document.EncryptionSystem));
        System.Console.WriteLine(string.Format("Pages count : {0}", document.Pages.Count));
        System.Console.WriteLine(string.Format("Title       : {0}", document.DocumentInformation.Title));
        System.Console.WriteLine(string.Format("Author      : {0}", document.DocumentInformation.Author));
        System.Console.WriteLine(string.Format("Creator     : {0}", document.DocumentInformation.Creator));
        System.Console.WriteLine(string.Format("Producer    : {0}", document.DocumentInformation.Producer));
        System.Console.WriteLine(string.Format("Subject     : {0}", document.DocumentInformation.Subject));
        if (document.DocumentInformation.CreationDate != System.DateTime.MinValue)
            System.Console.WriteLine(string.Format("CreationDate: {0}", document.DocumentInformation.CreationDate));
        if (document.DocumentInformation.ModifyDate != System.DateTime.MinValue)
            System.Console.WriteLine(string.Format("ModifyDate  : {0}", document.DocumentInformation.ModifyDate));

        // for each page of PDF document
        Vintasoft.Imaging.Pdf.Tree.PdfPage page;
        for (int i = 0; i < document.Pages.Count; i++)
        {
            // show information about PDF page
            System.Console.WriteLine();
            page = document.Pages[i];
            System.Console.WriteLine(string.Format("Page {0}:", i));
            System.Console.WriteLine(string.Format(" - Size (in units)    = {0}", page.Size));
            System.Console.WriteLine(string.Format(" - Default Resolution = {0}", page.DefaultResolution));
            Vintasoft.Imaging.Pdf.Tree.PdfImageResource[] images = page.GetImages();
            if (images.Length > 0)
                System.Console.WriteLine(string.Format(" - Contains {0} images.", images.Length));
            if (page.Thumbnail != null)
                System.Console.WriteLine(" - Contains thumbnail.");
            if (page.IsImageOnly)
                System.Console.WriteLine(" - Is image only page.");
        }
    }
}

Public Shared Sub GetInfoAboutPDF(filename As String)
    ' open PDF document
    Using document As New Vintasoft.Imaging.Pdf.PdfDocument(filename)
        ' show information about PDF document
        If document.IsEncrypted Then
            System.Console.WriteLine(String.Format("Encryption  : {0}", document.EncryptionSystem))
        End If
        System.Console.WriteLine(String.Format("Pages count : {0}", document.Pages.Count))
        System.Console.WriteLine(String.Format("Title       : {0}", document.DocumentInformation.Title))
        System.Console.WriteLine(String.Format("Author      : {0}", document.DocumentInformation.Author))
        System.Console.WriteLine(String.Format("Creator     : {0}", document.DocumentInformation.Creator))
        System.Console.WriteLine(String.Format("Producer    : {0}", document.DocumentInformation.Producer))
        System.Console.WriteLine(String.Format("Subject     : {0}", document.DocumentInformation.Subject))
        If document.DocumentInformation.CreationDate <> System.DateTime.MinValue Then
            System.Console.WriteLine(String.Format("CreationDate: {0}", document.DocumentInformation.CreationDate))
        End If
        If document.DocumentInformation.ModifyDate <> System.DateTime.MinValue Then
            System.Console.WriteLine(String.Format("ModifyDate  : {0}", document.DocumentInformation.ModifyDate))
        End If

        ' for each page of PDF document
        Dim page As Vintasoft.Imaging.Pdf.Tree.PdfPage
        For i As Integer = 0 To document.Pages.Count - 1
            ' show information about PDF page
            System.Console.WriteLine()
            page = document.Pages(i)
            System.Console.WriteLine(String.Format("Page {0}:", i))
            System.Console.WriteLine(String.Format(" - Size (in units)    = {0}", page.Size))
            System.Console.WriteLine(String.Format(" - Default Resolution = {0}", page.DefaultResolution))
            Dim images As Vintasoft.Imaging.Pdf.Tree.PdfImageResource() = page.GetImages()
            If images.Length > 0 Then
                System.Console.WriteLine(String.Format(" - Contains {0} images.", images.Length))
            End If
            If page.Thumbnail IsNot Nothing Then
                System.Console.WriteLine(" - Contains thumbnail.")
            End If
            If page.IsImageOnly Then
                System.Console.WriteLine(" - Is image only page.")
            End If
        Next
    End Using
End Sub