iTextSharp.text.pdf.PdfReader.GetPageContent C# (CSharp) Метод

        public byte[] GetPageContent(int pageNum, RandomAccessFileOrArray file) {
            PdfDictionary page = GetPageNRelease(pageNum);
            if (page == null)
                return null;
            PdfObject contents = GetPdfObjectRelease(page.Get(PdfName.CONTENTS));
            if (contents == null)
                return new byte[0];
            MemoryStream bout = null;
            if (contents.IsStream()) {
                return GetStreamBytes((PRStream)contents, file);
            }
            else if (contents.IsArray()) {
                PdfArray array = (PdfArray)contents;
                bout = new MemoryStream();
                for (int k = 0; k < array.Size; ++k) {
                    PdfObject item = GetPdfObjectRelease(array[k]);
                    if (item == null || !item.IsStream())
                        continue;
                    byte[] b = GetStreamBytes((PRStream)item, file);
                    bout.Write(b, 0, b.Length);
                    if (k != array.Size - 1)
                        bout.WriteByte((byte)'\n');
                }
                return bout.ToArray();
            }
            else
                return new byte[0];
        }
        

 /// <summary>
 /// Removes layers from a PDF document </summary>
 /// <param name="reader">	a PdfReader containing a PDF document </param>
 /// <param name="layers">	a sequence of names of OCG layers </param>
 /// <exception cref="IOException"> </exception>
 public virtual void RemoveLayers(PdfReader reader, params string[] layers)
 {
     int n = reader.NumberOfPages;
     for (int i = 1; i <= n; i++)
         reader.SetPageContent(i, reader.GetPageContent(i));
     ICollection<string> ocgs = new HashSet2<string>();
     for (int i = 0; i < layers.Length; i++)
     {
         ocgs.Add(layers[i]);
     }
     OCGParser parser = new OCGParser(ocgs);
     for (int i = 1; i <= n; i++)
     {
         PdfDictionary page = reader.GetPageN(i);
         Parse(parser, page);
         page.Remove(new PdfName("PieceInfo"));
         RemoveAnnots(page, ocgs);
         RemoveProperties(page, ocgs);
     }
     PdfDictionary root = reader.Catalog;
     PdfDictionary ocproperties = root.GetAsDict(PdfName.OCPROPERTIES);
     if (ocproperties != null) {
         RemoveOCGsFromArray(ocproperties, PdfName.OCGS, ocgs);
         PdfDictionary d = ocproperties.GetAsDict(PdfName.D);
         if (d != null) {
             RemoveOCGsFromArray(d, PdfName.ON, ocgs);
             RemoveOCGsFromArray(d, PdfName.OFF, ocgs);
             RemoveOCGsFromArray(d, PdfName.LOCKED, ocgs);
             RemoveOCGsFromArray(d, PdfName.RBGROUPS, ocgs);
             RemoveOCGsFromArray(d, PdfName.ORDER, ocgs);
             RemoveOCGsFromArray(d, PdfName.AS, ocgs);
         }
     }
     reader.RemoveUnusedObjects();
 }