public Watcher(IMessageSender <BusMessage> sender, IDirectoryWatcher directoryWatcher, IFileManager fileManager, bool?isDelete) { _sender = sender ?? throw new ArgumentNullException(nameof(sender)); _directoryWatcher = directoryWatcher ?? throw new ArgumentNullException(nameof(directoryWatcher)); _fileManager = fileManager ?? throw new ArgumentNullException(nameof(fileManager)); if (isDelete != null) { _shouldDelete = (bool)isDelete; } _directoryWatcher.NewFile += OnNewFile; _directoryWatcher.BeginWatch(); }