Introduction

public static void GetDocumentInformations()
{
  Console.WriteLine( "=== GET DOCUMENT INFORMATIONS ===" );
  var filename = "TikainAction.pdf";

  // Loads a PdfDocument.
  using( var pdfDoc = PdfDocument.Load( PdfDocumentsSample.PdfDocumentsSampleResourceDirectory + filename ) )
  {
    var outputFileName = "GetDocumentInformations.pdf";
    var outputPath = PdfDocumentsSample.PdfDocumentsSampleOutputDirectory + outputFileName;

    // Creates a PdfDocument.
    using( var pdfoutput = PdfDocument.Create( outputPath ) )
    {
      // Gets the first Page of the document.
      var page = pdfoutput.Pages.First();

      // Adds a title.
      var titleStyle = TextStyle.WithFont( pdfoutput.Fonts.GetStandardFont( StandardFontType.Helvetica ), 15d );
      page.AddParagraph( "Get Document Informations", titleStyle, new ParagraphStyle( ParagraphHorizontalAlignment.Center ) );

      // Adds red Courier text at a specific Y position.
      var redTextStyle = TextStyle.WithFontAndColor( pdfoutput.Fonts.GetStandardFont( StandardFontType.Courier ), 12d, Brushes.Red );
      page.AddParagraph( $"Printing Document info from: {filename}", 40, redTextStyle );

      // Adds Courier Text at a specific Y position.
      var textStyle = TextStyle.WithFont( pdfoutput.Fonts.GetStandardFont( StandardFontType.Courier ), 12d );
      page.AddParagraph( $"PDF Version: {pdfDoc.Version}", 90, textStyle );
      page.AddParagraph( $"Total pages: {pdfDoc.Pages.Count}", 105, textStyle );

      if( pdfDoc.Informations != null )
      {
        // Adds text with the metadata DocumentInformations.
        page.AddParagraph( $"Title: {pdfDoc.Informations.Title ?? "N/A"}", 120, textStyle );
        page.AddParagraph( $"Author: {pdfDoc.Informations.Author ?? "N/A"}", 135, textStyle );
        page.AddParagraph( $"Subject: {pdfDoc.Informations.Subject ?? "N/A"}", 150, textStyle );
        page.AddParagraph( $"Creator: {pdfDoc.Informations.Creator ?? "N/A"}", 165, textStyle );
        page.AddParagraph( $"Producer: {pdfDoc.Informations.Producer ?? "N/A"}", 180, textStyle );
        page.AddParagraph( $"Creation date: {pdfDoc.Informations.CreationDate?.ToString( CultureInfo.InvariantCulture ) ?? "N/A"}", 195, textStyle );
        page.AddParagraph( $"Modification date: {pdfDoc.Informations.ModifiedDate?.ToString( CultureInfo.InvariantCulture ) ?? "N/A"}", 210, textStyle );
      }

      // Saves the output document.
      pdfoutput.Save();
      Console.WriteLine( $"Info exported to path: {outputFileName}" );
    }
  }
}