public async Task <IActionResult> OnGetAsync(int?id)
        {
            if (id == null)
            {
                return(NotFound());
            }

            StudentEnrollment = await _context.StudentEnrollments
                                .Include(s => s.Course)
                                .Include(s => s.Student).SingleOrDefaultAsync(m => m.Id == id);

            if (StudentEnrollment == null)
            {
                return(NotFound());
            }
            return(Page());
        }
        public async Task <IActionResult> OnPostAsync(int?id)
        {
            if (id == null)
            {
                return(NotFound());
            }

            StudentEnrollment = await _context.StudentEnrollments.FindAsync(id);

            if (StudentEnrollment != null)
            {
                _context.StudentEnrollments.Remove(StudentEnrollment);
                await _context.SaveChangesAsync();
            }

            return(RedirectToPage("./Index"));
        }
        public async Task <IActionResult> OnGetAsync(int?id)
        {
            if (id == null)
            {
                return(NotFound());
            }

            StudentEnrollment = await _context.StudentEnrollments
                                .Include(s => s.Course)
                                .Include(s => s.Student).SingleOrDefaultAsync(m => m.Id == id);

            if (StudentEnrollment == null)
            {
                return(NotFound());
            }
            ViewData["CourseId"]  = new SelectList(_context.Courses, "Id", "Name");
            ViewData["StudentId"] = new SelectList(_context.Students, "Id", "FirstName");
            return(Page());
        }