public static Byte[] GeneratePdf(String pdfPath, IDictionary<String, String> formFieldMap) { Byte[] byteArray = null; using (var ms = new MemoryStream()) { var reader = new PdfReader(pdfPath); using (var stamper = new PdfStamper(reader, ms)) { stamper.SecurePdf(); var formFields = stamper.AcroFields; foreach (var fieldName in formFieldMap.Keys) { formFields.SetField(fieldName, formFieldMap[fieldName]); } stamper.FormFlattening = true; } byteArray = ms.ToArray(); reader.Close(); } return byteArray; }