public async Task <List <PlaylistItemData> > GetPlaylistItems(string playlistId) => await PlaylistItems.Where(x => x.PlaylistDataId == playlistId).ToListAsync();
/// <summary> /// Delete any songs in this playlist that are contained in the supplied collection /// </summary> /// <param name="songIds"></param> public void DeleteMatchingSongs(HashSet <int> songIds) => DeletePlaylistItems(PlaylistItems.Where(item => songIds.Contains((( SongPlaylistItem )item).SongId) == true));