Downloads the data of the specified document ID.
public static long DownloadDocument(DownloadDocumentOptions options)
options
Options containing the document properties and download options to use. This value must not be null.
The total number of bytes read into DownloadDocumentOptions.Data or DownloadDocumentOptions.Stream. This can be less than the number of bytes requested by DownloadDocumentOptions.Length, if that many bytes are not currently available, or zero (0) if the end of the data has been reached.
Similar to UploadDocument, data can be downloaded in chunks or all at once. Refer to Uploading Using the Document Library for detailed information on how to use these methods and the various options used.
GetDocumentCacheInfo can be used to determine if a document is in the cache and to get its information.
DownloadAnnotations can be used to download the annotations of a document (if any).
This example will show how to download the data of a document stored in the cache into a stream all at once and then buffer array using chunks.
using Leadtools;using Leadtools.Codecs;using Leadtools.Document.Writer;using Leadtools.Document;using Leadtools.Caching;using Leadtools.Annotations.Engine;using Leadtools.Ocr;using Leadtools.Barcode;using Leadtools.Document.Converter;public void DownloadDocumentExample(){var documentUri = new Uri("https://demo.leadtools.com/images/pdf/leadtools.pdf");string documentFile1 = Path.Combine(LEAD_VARS.ImagesDir, "downloaded1.pdf");string documentFile2 = Path.Combine(LEAD_VARS.ImagesDir, "downloaded2.pdf");// Setup a cacheFileCache cache = new FileCache();cache.CacheDirectory = @"c:\cache-dir";string documentId;// Load a document into the cachevar loadDocumentOptions = new LoadDocumentOptions();loadDocumentOptions.Cache = cache;using (var document = DocumentFactory.LoadFromUri(documentUri, loadDocumentOptions)){// Get its document ID and save itdocumentId = document.DocumentId;document.AutoDeleteFromCache = false;document.AutoSaveToCache = false;document.SaveToCache();}// Now download it all at once into a memory streamvar downloadDocumentOptions = new DownloadDocumentOptions();downloadDocumentOptions.Cache = cache;downloadDocumentOptions.DocumentId = documentId;downloadDocumentOptions.Offset = 0;downloadDocumentOptions.Length = -1;using (var stream = new MemoryStream()){downloadDocumentOptions.Stream = stream;long bytes = DocumentFactory.DownloadDocument(downloadDocumentOptions);Console.WriteLine("Downloaded {0} bytes into the stream", bytes);long annotations = DocumentFactory.DownloadAnnotations(downloadDocumentOptions);Console.WriteLine(annotations + " annotations downloaded");// The following method is obsolete. Use DownloadAnnotations(DownloadDocumentOptions) insteadint annotations2 = DocumentFactory.DownloadAnnotations(downloadDocumentOptions.Cache, downloadDocumentOptions.DocumentId, downloadDocumentOptions.Offset, (int)bytes, stream);Console.WriteLine(annotations2 + " annotations downloaded");// Save the stream to a file and show itusing (var output = File.Create(documentFile1))stream.WriteTo(output);Process.Start(documentFile1);}// Download it again, this time we will buffer it 32K at a timedownloadDocumentOptions = new DownloadDocumentOptions();downloadDocumentOptions.Cache = cache;downloadDocumentOptions.DocumentId = documentId;byte[] buffer = new byte[1024 * 32];using (var output = File.Create(documentFile2)){// Offset to where we are:long offset = 0;int bytes;do{downloadDocumentOptions.Offset = offset;downloadDocumentOptions.Length = buffer.Length;downloadDocumentOptions.Data = buffer;downloadDocumentOptions.DataOffset = 0;bytes = (int)DocumentFactory.DownloadDocument(downloadDocumentOptions);if (bytes > 0){Console.WriteLine("Downloaded {0} bytes into the buffer", bytes);// Next chunkoffset += bytes;output.Write(buffer, 0, bytes);// The following method is obsolete. Use DownloadAnnotations(DownloadDocumentOptions) insteadint annotations = DocumentFactory.DownloadAnnotations(downloadDocumentOptions.Cache, downloadDocumentOptions.DocumentId, downloadDocumentOptions.Offset, buffer, downloadDocumentOptions.DataOffset, buffer.Length);Console.WriteLine(annotations + " annotations downloaded");}}while (bytes > 0);}Process.Start(documentFile2);// We are done, clean upvar deleteFromCacheOptions = new LoadFromCacheOptions();deleteFromCacheOptions.Cache = cache;deleteFromCacheOptions.DocumentId = documentId;DocumentFactory.DeleteFromCache(deleteFromCacheOptions);}static class LEAD_VARS{public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images";}