public IActionResult EditCourses(int?id) { if (id == null) { return(View("NotFound")); } ViewBag.StudentId = id.Value; var CoursesList = coursesRepository.GetAllCourses(); var model = new List <EditStudentCoursesViewModel>(); foreach (var item in CoursesList) { var editStudentCoursesViewModel = new EditStudentCoursesViewModel { CourseId = item.CourseId, CourseName = item.Name, CourseCode = item.Code, CourseHours = item.Hours }; if (studentCourseRepository.IsRelationExist(id.Value, item.CourseId)) { editStudentCoursesViewModel.IsSelected = true; } else { editStudentCoursesViewModel.IsSelected = false; } model.Add(editStudentCoursesViewModel); } return(View(model)); }