DownloadAnnotations(DownloadDocumentOptions) Method (original) (raw)
Summary
Downloads the annotations of the specified document.
Example
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 cache
FileCache cache = new FileCache();
cache.CacheDirectory = @"c:\cache-dir";
string documentId;
// Load a document into the cache
var loadDocumentOptions = new LoadDocumentOptions();
loadDocumentOptions.Cache = cache;
using (var document = DocumentFactory.LoadFromUri(documentUri, loadDocumentOptions))
{
// Get its document ID and save it
documentId = document.DocumentId;
document.AutoDeleteFromCache = false;
document.AutoSaveToCache = false;
document.SaveToCache();
}
// Now download it all at once into a memory stream
var 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// The following method is obsolete.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) instead
int 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 it
using (var output = File.Create(documentFile1))
stream.WriteTo(output);
Process.Start(documentFile1);
}
// Download it again, this time we will buffer it 32K at a time
downloadDocumentOptions = 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 chunk
offset += bytes;
output.Write(buffer, 0, bytes);
// The following method is obsolete. Use DownloadAnnotations(DownloadDocumentOptions) instead
int 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 up
var deleteFromCacheOptions = new LoadFromCacheOptions();
deleteFromCacheOptions.Cache = cache;
deleteFromCacheOptions.DocumentId = documentId;
DocumentFactory.DeleteFromCache(deleteFromCacheOptions);
}
static class LEAD_VARS
{
public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images";
}