public void Visit(PdfInteger integer)
 {
     Append(integer);
 }
Exemple #2
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        public void Load(Stream stream, bool immediate = false, byte[] bytes = null)
        {
            if (_open)
            {
                throw new ApplicationException("Document already has a stream open.");
            }

            _stream = stream;
            _parser = new Parser(_stream);
            _parser.ResolveReference += Parser_ResolveReference;

            // PDF file should have a well known marker at top of file
            _parser.ParseHeader(out int versionMajor, out int versionMinor);
            Version = new PdfVersion(this, versionMajor, versionMinor);

            // Find stream position of the last cross-reference table
            long xRefPosition = _parser.ParseXRefOffset();
            bool lastHeader   = true;

            do
            {
                // Get the aggregated set of entries from all the cross-reference table sections
                List <TokenXRefEntry> xrefs = _parser.ParseXRef(xRefPosition);

                // Should always be positioned at the trailer after parsing cross-table references
                PdfDictionary trailer = new PdfDictionary(this, _parser.ParseTrailer());
                PdfInteger    size    = trailer.MandatoryValue <PdfInteger>("Size");
                foreach (TokenXRefEntry xref in xrefs)
                {
                    // Ignore unused entries and entries smaller than the defined size from the trailer dictionary
                    if (xref.Used && (xref.Id < size.Value))
                    {
                        IndirectObjects.AddXRef(xref);
                    }
                }

                if (lastHeader)
                {
                    // Replace the default decryption handler with one from the document settings
                    DecryptHandler = PdfDecrypt.CreateDecrypt(this, trailer);

                    // We only care about the latest defined catalog and information dictionary
                    _refCatalog = trailer.MandatoryValue <PdfObjectReference>("Root");
                    _refInfo    = trailer.OptionalValue <PdfObjectReference>("Info");
                }

                // If there is a previous cross-reference table, then we want to process that as well
                PdfInteger prev = trailer.OptionalValue <PdfInteger>("Prev");
                if (prev != null)
                {
                    xRefPosition = prev.Value;
                }
                else
                {
                    xRefPosition = 0;
                }

                lastHeader = false;
            } while (xRefPosition > 0);

            _open = true;

            // Must load all objects immediately so the stream can then be closed
            if (immediate)
            {
                // Is there enough work to justify using multiple threads
                if ((bytes != null) && (IndirectObjects.Count > BACKGROUND_TRIGGER))
                {
                    // Setup the synchronization event so we wait until all work is completed
                    _backgroundCount = NUM_BACKGROUND_ITEMS;
                    _backgroundEvent = new ManualResetEvent(false);

                    List <int> ids       = IndirectObjects.Ids.ToList();
                    int        idCount   = ids.Count;
                    int        batchSize = idCount / NUM_BACKGROUND_ITEMS;

                    for (int i = 0, index = 0; i < NUM_BACKGROUND_ITEMS; i++, index += batchSize)
                    {
                        // Create a parser per unit of work, so they can work in parallel
                        MemoryStream memoryStream = new MemoryStream(bytes);
                        Parser       parser       = new Parser(memoryStream);

                        // Make sure the last batch includes all the remaining Ids
                        ThreadPool.QueueUserWorkItem(BackgroundResolveReference, new BackgroundArgs()
                        {
                            Parser = parser,
                            Ids    = ids,
                            Index  = index,
                            Count  = (i == (NUM_BACKGROUND_ITEMS - 1)) ? idCount - index : batchSize
                        });
                    }

                    _backgroundEvent.WaitOne();
                    _backgroundEvent.Dispose();
                    _backgroundEvent = null;
                }
                else
                {
                    IndirectObjects.ResolveAllReferences(this);
                }

                Close();
            }
        }