iTextSharp.text.pdf.PdfStamperImp.AddDocumentField C# (CSharp) Метод

        internal void AddDocumentField(PdfIndirectReference ref_p)
        {
            PdfDictionary catalog = reader.Catalog;
            PdfDictionary acroForm = (PdfDictionary)PdfReader.GetPdfObject(catalog.Get(PdfName.ACROFORM), catalog);
            if (acroForm == null) {
                acroForm = new PdfDictionary();
                catalog.Put(PdfName.ACROFORM, acroForm);
                MarkUsed(catalog);
            }
            PdfArray fields = (PdfArray)PdfReader.GetPdfObject(acroForm.Get(PdfName.FIELDS), acroForm);
            if (fields == null) {
                fields = new PdfArray();
                acroForm.Put(PdfName.FIELDS, fields);
                MarkUsed(acroForm);
            }
            if (!acroForm.Contains(PdfName.DA)) {
                acroForm.Put(PdfName.DA, new PdfString("/Helv 0 Tf 0 g "));
                MarkUsed(acroForm);
            }
            fields.Add(ref_p);
            MarkUsed(fields);
        }