public async Task <IActionResult> Edit(int id, [Bind("id,subject_id,teacher_id")] subject_teachers subject_teachers)
        {
            if (id != subject_teachers.id)
            {
                return(NotFound());
            }

            if (ModelState.IsValid)
            {
                try
                {
                    _context.Update(subject_teachers);
                    await _context.SaveChangesAsync();
                }
                catch (DbUpdateConcurrencyException)
                {
                    if (!subject_teachersExists(subject_teachers.id))
                    {
                        return(NotFound());
                    }
                    else
                    {
                        throw;
                    }
                }
                return(RedirectToAction(nameof(Index)));
            }
            ViewData["subject_id"] = new SelectList(_context.subject, "id", "id", subject_teachers.subject_id);
            ViewData["teacher_id"] = new SelectList(_context.teachers, "id", "id", subject_teachers.teacher_id);
            return(View(subject_teachers));
        }
        public async Task <IActionResult> Create([Bind("id,subject_id,teacher_id")] subject_teachers subject_teachers)
        {
            if (ModelState.IsValid)
            {
                _context.Add(subject_teachers);
                await _context.SaveChangesAsync();

                return(RedirectToAction(nameof(Index)));
            }
            ViewData["subject_id"] = new SelectList(_context.subject, "id", "id", subject_teachers.subject_id);
            ViewData["teacher_id"] = new SelectList(_context.teachers, "id", "id", subject_teachers.teacher_id);
            return(View(subject_teachers));
        }