// GET: Songs
public async Task <IActionResult> Index(string songGenre, string titleString, string artistString,
string albumString)
{
// LINQ to obtain a list of genres for a selectList for users
IQueryable <string> genreQuery = from s in _context.Song
orderby s.Genre
select s.Genre;
// LINQ to select songs
var songs = from s in _context.Song
select s;
// query for song title
if (!string.IsNullOrEmpty(titleString))
{
songs = songs.Where(s => s.Title.Contains(titleString));
}
// query for song's Genre
if (!string.IsNullOrEmpty(songGenre))
{
songs = songs.Where(s => s.Genre == songGenre);
}
// query for artist
if (!string.IsNullOrEmpty(artistString))
{
songs = songs.Where(s => s.Artist.Contains(artistString));
}
// query for album
if (!string.IsNullOrEmpty(albumString))
{
songs = songs.Where(s => s.Album.Contains(albumString));
}
// create a song genre view model to be rendered based on client choice
var songGenreViewModel = new SongGenreViewModel();
// only assign the view model if a query is created, and use distinct to ensure no duplicates
songGenreViewModel.genres = new SelectList(await genreQuery.Distinct().ToListAsync());
// also update songs list to reflect query
songGenreViewModel.songs = await songs.ToListAsync();
return(View(songGenreViewModel));
}
public SongGenreViewModel GetSongGenre(int id)
{
var songGenre = this.DbContext
.SongGenres
.Include(x => x.Songs)
.FirstOrDefault(x => x.Id == id);
if (songGenre == null)
{
return(null);
}
var songGenreModel = new SongGenreViewModel()
{
GenreName = songGenre.GenreName,
Songs = this.Mapper.Map <ICollection <SongConciseViewModel> >(songGenre.Songs)
};
return(songGenreModel);
}