public override string ToString() { string trackString = "[Unknown Track]"; if (TrackNumbers != null && TrackNumbers.Any()) { trackString = string.Format("{0}", string.Join("-", TrackNumbers.Select(c => c.ToString("00")))); } return(string.Format("{0} - {1} - {2}:{3} {4}: {5}", Authors.ConcatToString(" & "), BookTitle, DiscNumber, trackString, Title, Quality)); }