public async Task <IActionResult> Edit(int id, [Bind("Id,Name,Surname,ClassId")] Student student)
        {
            if (id != student.Id)
            {
                return(NotFound());
            }

            if (ModelState.IsValid)
            {
                try
                {
                    _context.Update(student);
                    await _context.SaveChangesAsync();
                }
                catch (DbUpdateConcurrencyException)
                {
                    if (!StudentExists(student.Id))
                    {
                        return(NotFound());
                    }
                    else
                    {
                        throw;
                    }
                }
                return(RedirectToAction(nameof(Index)));
            }
            ViewData["ClassId"] = new SelectList(_context.Class, "Id", "Id", student.ClassId);
            return(View(student));
        }
        public async Task <IActionResult> Edit(int id, [Bind("Id,Value,Description,StudentId")] Mark mark)
        {
            if (id != mark.Id)
            {
                return(NotFound());
            }

            if (ModelState.IsValid)
            {
                try
                {
                    _context.Update(mark);
                    await _context.SaveChangesAsync();
                }
                catch (DbUpdateConcurrencyException)
                {
                    if (!MarkExists(mark.Id))
                    {
                        return(NotFound());
                    }
                    else
                    {
                        throw;
                    }
                }
                return(RedirectToAction(nameof(Index)));
            }
            ViewData["StudentId"] = new SelectList(_context.Student, "Id", "Id", mark.StudentId);
            return(View(mark));
        }