Beispiel #1
0
        /// <summary>
        ///  Extracts words from a document content read with <paramref name="sourceReader"/> and returns them as an observable sequence
        /// </summary>
        /// <param name="sourceReader">The reader to read the document content from</param>
        /// <returns>Observable sequence with a document words, one by one</returns>
        /// <remarks>
        ///  Reads the content from the <paramref name="sourceReader"/> line by line and extracts words from each line
        ///  with the specified <see cref="ILineParser"/> instance.
        /// </remarks>
        public IObservable <string> ExtractWords([NotNull] TextReader sourceReader)
        {
            if (sourceReader == null)
            {
                throw new ArgumentNullException("sourceReader");
            }

            if (!UseAsync)
            {
                return(Observable.Create <string>(obs =>
                {
                    var scheduler = Scheduler.Default;
                    var subscription = new SingleAssignmentDisposable();
                    subscription.Disposable = scheduler.Schedule(() =>
                    {
                        try
                        {
                            while (!subscription.IsDisposed)
                            {
                                var line = sourceReader.ReadLine();
                                if (line == null)
                                {
                                    break;
                                }
                                foreach (var word in lineParser.ExtractWords(line))
                                {
                                    obs.OnNext(word);
                                }
                            }
                            obs.OnCompleted();
                        }
                        catch (Exception e)
                        {
                            obs.OnError(e);
                        }
                    });
                    return subscription;
                }));
            }
            else
            {
                // async version is much more slower
                return(Observable.Create <string>(async(obs, cancel) =>
                {
                    try
                    {
                        while (!cancel.IsCancellationRequested)
                        {
                            var line = await sourceReader.ReadLineAsync().ConfigureAwait(false);
                            if (line == null)
                            {
                                break;
                            }
                            foreach (var word in lineParser.ExtractWords(line))
                            {
                                obs.OnNext(word);
                            }
                        }
                        obs.OnCompleted();
                    }
                    catch (Exception e)
                    {
                        obs.OnError(e);
                    }
                }).SubscribeOn(Scheduler.Default));
            }
        }