private void addAsAttachment(IDataExporter exporter, byte[] data)
{
if (string.IsNullOrEmpty(exporter.FileName))
throw new InvalidOperationException("Please fill the exporter.FileName.");
if (string.IsNullOrEmpty(exporter.Description))
exporter.Description = "Exported data";
var pdfDictionary = new PdfDictionary();
pdfDictionary.Put(PdfName.MODDATE, new PdfDate(DateTime.Now));
var fs = PdfFileSpecification.FileEmbedded(_sharedData.PdfWriter, null, exporter.FileName, data, true, null, pdfDictionary);
_sharedData.PdfWriter.AddFileAttachment(exporter.Description, fs);
}