private void ExplicitLoading3()
{
//This is not allowed
//db.Entry(album).Collection(t => t.Track.Where(f => f.Name.StartsWith("A"))).Load();
using (ChinookContext db = new ChinookContext())
{
var Albums = db.Album.Take(5).ToList();
foreach (var album in Albums)
{
db.Entry(album).Collection(t => t.Track).Query().Where(f => f.Name.Contains("The")).Load();
db.Entry(album).Reference(t => t.Artist).Query().Load();
//Also works
//db.Entry(album).Collection(t => t.Track).Query().Where(f => f.Name.Contains("The")).ToList();
//db.Entry(album).Reference(t => t.Artist).Query().ToList();
Console.WriteLine("{0} {1}", album.Title, album.Artist.Name);
foreach (var track in album.Track)
{
Console.WriteLine("\t\t\t{0}", track.Name);
}
}
}
Console.WriteLine("Press any key to continue");
Console.ReadKey();
}
private void ExplicitLoading2()
{
using (ChinookContext db = new ChinookContext())
{
var Albums = db.Album.Take(5).ToList();
foreach (var album in Albums)
{
db.Entry(album).Collection(t => t.Track).Load();
db.Entry(album).Reference(t => t.Artist).Load();
Console.WriteLine("{0} {1}", album.Title, album.Artist.Name);
foreach (var track in album.Track)
{
Console.WriteLine("\t\t\t{0}", track.Name);
}
}
}
Console.WriteLine("Press any key to continue");
Console.ReadKey();
//SELECT TOP(@__p_0) [a].[AlbumId], [a].[ArtistId], [a].[Title]
//FROM [Album] AS [a]
//SELECT [t].[TrackId], [t].[AlbumId], [t].[Bytes], [t].[Composer], [t].[GenreId], [t].[MediaTypeId], [t].[Milliseconds], [t].[Name], [t].[UnitPrice]
//FROM [Track] AS [t]
//WHERE [t].[AlbumId] = @__p_0
//SELECT [a].[ArtistId], [a].[Name]
//FROM [Artist] AS [a]
//WHERE [a].[ArtistId] = @__p_0
}
public async Task <IActionResult> PutTracks([FromRoute] long id, [FromBody] Tracks tracks)
{
if (!ModelState.IsValid)
{
return(BadRequest(ModelState));
}
if (id != tracks.TrackId)
{
return(BadRequest());
}
_context.Entry(tracks).State = EntityState.Modified;
try
{
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!TracksExists(id))
{
return(NotFound());
}
else
{
throw;
}
}
return(NoContent());
}
public async Task <IActionResult> PutArtista(int id, Artista artista)
{
if (id != artista.ArtistaId)
{
return(BadRequest());
}
_context.Entry(artista).State = EntityState.Modified;
try
{
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!ArtistaExists(id))
{
return(NotFound());
}
else
{
throw;
}
}
return(NoContent());
}
public async Task <IActionResult> PutCancion(int id, Cancion cancion)
{
if (id != cancion.CancionId)
{
return(BadRequest());
}
_context.Entry(cancion).State = EntityState.Modified;
try
{
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!CancionExists(id))
{
return(NotFound());
}
else
{
throw;
}
}
return(NoContent());
}
//// Daten anlegen
static void Main(string[] args)
{
using (ChinookContext context = new ChinookContext())
{
context.Database.Log = Console.WriteLine;
Artist artist = new Artist()
{
Name = "Hosen"
};
//Album album = new Album() { Artist = artist, Title = "Atmen" };
artist.Albums.Add(new Album()
{
Title = "Gürtelrose"
});
Console.WriteLine(context.Entry(artist).State);
// Neu erzeugtes Element dem Context hinzufügen
context.Artists.Add(artist);
//context.Albums.Add(album);
context.SaveChanges();
//Console.WriteLine(context.Entry(artist).State);
}
Console.ReadKey();
}
public async Task <IActionResult> PutAlbum([FromRoute] int id, [FromBody] Album album)
{
if (!ModelState.IsValid)
{
return(BadRequest(ModelState));
}
if (id != album.AlbumId)
{
return(BadRequest());
}
_context.Entry(album).State = EntityState.Modified;
try
{
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!AlbumExists(id))
{
return(NotFound());
}
else
{
throw;
}
}
return(NoContent());
}
}//eom
public void DeleteTracks(string username, string playlistname, List <int> trackstodelete)
{
using (var context = new ChinookContext())
{
Playlist exists = (from x in context.Playlists
where x.UserName.Equals(username, StringComparison.OrdinalIgnoreCase) &&
x.Name.Equals(playlistname, StringComparison.OrdinalIgnoreCase)
select x).FirstOrDefault();
if (exists == null)
{
throw new Exception("Playlist has been removed from the database.");
}
else
{
var trackskept = exists.PlaylistTracks.Where(tr => !trackstodelete.Any(tod => tod == tr.TrackId)).Select(tr => tr);
PlaylistTrack item = null;
foreach (int dtrack in trackstodelete)
{
item = exists.PlaylistTracks.Where(dx => dx.TrackId == dtrack).FirstOrDefault();
exists.PlaylistTracks.Remove(item);
}
int newrownumber = 1;
foreach (var trackkept in trackskept)
{
trackkept.TrackNumber = newrownumber;
context.Entry(trackkept).Property(y => y.TrackNumber).IsModified = true;
newrownumber++;
}
context.SaveChanges();
}
}
}//eom
public async Task <IActionResult> PutGenero(int id, Genero genero)
{
if (id != genero.GeneroId)
{
return(BadRequest());
}
_context.Entry(genero).State = EntityState.Modified;
try
{
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!GeneroExists(id))
{
return(NotFound());
}
else
{
throw;
}
}
return(NoContent());
}
public void UpdateTrack(Track info)
{
using (var context = new ChinookContext())
{
var existing = context.Entry(info);
existing.State = EntityState.Modified;
context.SaveChanges();
}
}
public void UpdateEmployee(Employee info)
{
using (var context = new ChinookContext())
{
DbEntityEntry <Employee> existing = context.Entry(info);
existing.State = System.Data.Entity.EntityState.Modified;
context.SaveChanges();
}
}
public async Task <ActionResult> Edit([Bind(Include = "AlbumId,Title,ArtistId")] Album album)
{
if (ModelState.IsValid)
{
db.Entry(album).State = EntityState.Modified;
await db.SaveChangesAsync();
return(RedirectToAction("Index"));
}
ViewBag.ArtistId = new SelectList(db.Artists, "ArtistId", "Name", album.ArtistId);
return(View(album));
}
public int Album_Update(Album item)
{
using (var context = new ChinookContext())
{
if (CheckReleaseYear(item))
{
//any additional logic
item.ReleaseLabel = string.IsNullOrEmpty(item.ReleaseLabel) ? null :
item.ReleaseLabel;
context.Entry(item).State = System.Data.Entity.EntityState.Modified; //staging
return(context.SaveChanges()); //commit to database AND RETURN ROWS AFFECTED.
}
else
{
throw new BusinessRuleException("Validation Error", reasons);
}
}
}
public void Albums_Update(Album item)
{
using (var context = new ChinookContext())
{
//any business rules
//any data refinements
//review of using iif
//composer cam be a mi;; stromg
//we do not wish to store an empty string
context.Albums.Attach(item);
item.ReleaseLabel = string.IsNullOrEmpty(item.ReleaseLabel) ? null : item.ReleaseLabel;
//update the existing instance of truckinfo on the database
context.Entry(item).State = EntityState.Modified;
//update command if updating selected fields
//context
context.SaveChanges();
}
}
public virtual async Task <bool> Modify(long id, TEntity entity)
{
_context.Entry(entity).State = EntityState.Modified;
try
{
await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
if (!EntityExists(id))
{
return(false);
}
else
{
throw;
}
}
return(true);
}
public void MoveTrack(string username, string playlistname, int trackid, int tracknumber, string direction)
{
using (var context = new ChinookContext())
{
Playlist exists = (from x in context.Playlists
where x.UserName.Equals(username, StringComparison.OrdinalIgnoreCase) &&
x.Name.Equals(playlistname, StringComparison.OrdinalIgnoreCase)
select x).FirstOrDefault();
if (exists == null)
{
throw new Exception("Playlist has been removed from the database.");
}
else
{
PlaylistTrack movetrack = (from x in exists.PlaylistTracks
where x.TrackId == trackid
select x).FirstOrDefault();
if (movetrack == null)
{
throw new Exception("Primary Playlist track has been removed from the database.");
}
else
{
PlaylistTrack othertrack = null;
if (direction.Equals("UP"))
{
othertrack = (from x in exists.PlaylistTracks
where x.TrackNumber == tracknumber - 1
select x).FirstOrDefault();
if (othertrack == null)
{
throw new Exception("Secondary Playlist track has been removed from the database.");
}
else
{
movetrack.TrackNumber -= 1;
othertrack.TrackNumber += 1;
}
}
else
{
othertrack = (from x in exists.PlaylistTracks
where x.TrackNumber == tracknumber + 1
select x).FirstOrDefault();
if (othertrack == null)
{
throw new Exception("Secondary Playlist track has been removed from the database.");
}
else
{
movetrack.TrackNumber += 1;
othertrack.TrackNumber -= 1;
}
}
context.Entry(movetrack).Property(y => y.TrackNumber).IsModified = true;
context.Entry(othertrack).Property(y => y.TrackNumber).IsModified = true;
context.SaveChanges();
}
}
}
}//eom
