public async Task <IActionResult> Edit(int id, MovieDirectorEditViewModel model)
 {
     if (ModelState.IsValid)
     {
         var director = _context.Directors.Find(id);
         director.MovieID     = model.MovieID;
         director.Name        = model.Name;
         director.DateOfBirth = model.DateOfBirth;
         _context.Update(director);
         await _context.SaveChangesAsync();
     }
     ViewData["MovieID"] = new SelectList(_context.Movies, "ID", "Titel", model.MovieID);
     return(RedirectToAction(nameof(Index)));
 }
        public async Task <IActionResult> Edit(int?id)
        {
            if (id == null)
            {
                return(NotFound());
            }

            var director = await _context.Directors.Include(d => d.Movies).FirstOrDefaultAsync(d => d.ID == id);

            if (director == null)
            {
                return(NotFound());
            }
            var model = new MovieDirectorEditViewModel()
            {
                ID = director.ID, Name = director.Name, DateOfBirth = director.DateOfBirth, MovieID = director.MovieID, Movies = director.Movies.Titel
            };

            ViewData["MovieID"] = new SelectList(_context.Movies, "ID", "Titel", director.MovieID);
            return(View(model));
        }