public async Task <IActionResult> EnrollMultiple(int?id)
{
var course = await _context.Course.Where(m => m.Id == id).Include(m => m.Students).FirstOrDefaultAsync();
var vm = new EnrollMultipleViewModel
{
StudentsList = new MultiSelectList(_context.Student.OrderBy(s => s.FirstName), "Id", "FullName"),
SelectedStudents = course.Students.Select(sa => sa.StudentId)
};
ViewData["CourseName"] = _context.Course.Where(c => c.Id == id).Select(c => c.Title).FirstOrDefault();
ViewData["chosenId"] = id;
return(View(vm));
}
public async Task <IActionResult> EnrollMultiple(int id, EnrollMultipleViewModel vm)
{
if (id != vm.NewEnrollment.CourseId)
{
return(NotFound());
}
IEnumerable <double> listStudents = vm.SelectedStudents;
IEnumerable <double> existStudents = _context.Enrollment.Where(s => listStudents.Contains(s.StudentId) && s.CourseId == id).Select(s => s.StudentId);
IEnumerable <double> newStudents = listStudents.Where(s => !existStudents.Contains(s));
foreach (double sid in newStudents)
{
_context.Enrollment.Add(new Enrollment {
StudentId = sid, CourseId = id, Year = vm.NewEnrollment.Year, Semester = vm.NewEnrollment.Semester
});
}
await _context.SaveChangesAsync();
return(RedirectToAction(nameof(Index)));
}