Extract PDF form field names from a PDF form

Question

I\'m using pdftk to fill in a PDF form with an XFDF file. However, for this project I do not know in advance what fields will be present, so I need to analyse the PDF itself

Answer 1

C# / ITextSharp

    public static void TracePdfFields(string pdfFilePath)
    {
        PdfReader pdfReader = new PdfReader(pdfFilePath);
        MemoryStream pdfStream = new MemoryStream();
        PdfStamper pdfStamper = new PdfStamper(pdfReader, pdfStream, '\0', true);

        int i = 1;
        foreach (var f in pdfStamper.AcroFields.Fields)
        {
            pdfStamper.AcroFields.SetField(f.Key, string.Format("{0} : {1}", i, f.Key));
            i++;
            //DoTrace("Field = [{0}] | Value = [{1}]", f.Key, f.Value.ToString());
        }
        pdfStamper.FormFlattening = false;
        pdfStamper.Writer.CloseStream = false;
        pdfStamper.Close();

        FileStream fs = File.OpenWrite(string.Format(@"{0}/{1}-TracePdfFields_{2}.pdf", 
            ConfigManager.GetInstance().LogConfig.Dir, 
            new FileInfo(pdfFilePath).Name, 
            DateTime.Now.Ticks));

        fs.Write(pdfStream.ToArray(), 0, (int)pdfStream.Length);
        fs.Flush();
        fs.Close();
    }