Indicates whether an entry associated with the specified document exists.
public bool HasDocument(string documentId,bool updateExpiry)
documentId
Document ID.
updateExpiry
Touches the item by updating its expiry policy.
true if the memory cache has an entry associated with documentId; otherwise, false.
If updateExpiry is true and the cache contains an entry associated with documentId, then the item expiry will be extended by another DocumentMemoryCacheStartOptions.SlidingExpiration.
Refer to DocumentMemoryCache for more information.
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 DocumentMemoryCacheExample(){// The cache we are usingFileCache cache = new FileCache();cache.PolicySerializationMode = CacheSerializationMode.Json;cache.DataSerializationMode = CacheSerializationMode.Json;cache.CacheDirectory = @"c:\cache-dir";// The document files we are usingstring[] documentFiles ={// PDF files are very fast to load and will not use memory cache@"C:\LEADTOOLS22\Resources\Images\leadtools.pdf",// Large Excel files are complex and loading may take some time, they could use memory cache@"C:\LEADTOOLS22\Resources\Images\complex.xlsx",};// First process without memory cache and obtain some timesLoadAndProcessDocument(documentFiles, cache);// Then process with memory cache// Document memory cache options to usevar documentMemoryCacheStartOptions = new DocumentMemoryCacheStartOptions{// Use for documents that take more than 2 seconds to load initiallyMinimumLoadDuration = TimeSpan.FromSeconds(2),// No maximum limit on the number of cache items to keep in memoryMaximumItems = 0,// Purse items from the cache if not touched for 60 secondsSlidingExpiration = TimeSpan.FromSeconds(60),// Check for expired items every 60 secondsTimerInterval = TimeSpan.FromSeconds(60)};// Use itDocumentFactory.DocumentMemoryCache.Start(documentMemoryCacheStartOptions);// Run again// For the first document, times should be very close to the since this is a PDF document and is very fast (less than MinimumLoadDuration)// For the second document, initial times should be the same, but loading all pages should be much fasterLoadAndProcessDocument(documentFiles, cache);// Clean upDocumentFactory.DocumentMemoryCache.Stop();}private static void LoadAndProcessDocument(string[] documentFiles, ObjectCache cache){Console.WriteLine($"Using memory cache is {DocumentFactory.DocumentMemoryCache.IsStarted}");string[] documentIds = new string[documentFiles.Length];var stopwatch = new Stopwatch();TimeSpan elapsed;for (var i = 0; i < documentFiles.Length; i++){string documentFile = documentFiles[i];int pageCount;// First try without memory cache and obtain some timesstopwatch.Restart();using (LEADDocument document = DocumentFactory.LoadFromFile(documentFile,new LoadDocumentOptions{Cache = cache})){document.Images.MaximumImagePixelSize = 2048;document.AutoSaveToCache = false;document.AutoDeleteFromCache = false;document.SaveToCache();documentIds[i] = document.DocumentId;pageCount = document.Pages.Count;}elapsed = stopwatch.Elapsed;Console.WriteLine($"Initial load from {Path.GetFileName(documentFile)} took ~{(int)elapsed.TotalSeconds} seconds");// Check if it's in the cacheConsole.WriteLine($"Is using memory cache is {DocumentFactory.DocumentMemoryCache.HasDocument(documentIds[i], false)}");// Next call LoadFromCache and process a page in multiple threadsstopwatch.Restart();LoadAllPagesInThreads(documentIds[i], pageCount, cache);elapsed = stopwatch.Elapsed;Console.WriteLine($"Multi-threaded load of all pages took ~{(int)elapsed.TotalSeconds} seconds");}// Clean upDeleteDocumentsFromCache(documentIds, cache);}private static void LoadAllPagesInThreads(string documentId, int pageCount, ObjectCache cache){System.Threading.Tasks.Parallel.For(1,pageCount + 1,new System.Threading.Tasks.ParallelOptions { MaxDegreeOfParallelism = 4 },(int pageNumber) =>{// Load the document from the cacheusing (LEADDocument document = DocumentFactory.LoadFromCache(new LoadFromCacheOptions{Cache = cache,DocumentId = documentId})){// Simulates processing of the pageDocumentPage documentPage = document.Pages[pageNumber - 1];using (RasterImage image = documentPage.GetImage()){}}});}private static void DeleteDocumentsFromCache(string[] documentIds, ObjectCache cache){foreach (string documentId in documentIds){DocumentFactory.DeleteFromCache(new LoadFromCacheOptions{Cache = cache,DocumentId = documentId,});}}