// GET: Instructor/Create
public ActionResult Create()
{
var instructor = new Instructor {Courses = new List<Course>()};
PopulateAssigmentCourseData(instructor);
return View();
}
private void UpdateInstructorCourses(Instructor instructorToUpdate, string[] selectedCoursesIds)
{
if (selectedCoursesIds == null || !selectedCoursesIds.Any())
{
instructorToUpdate.Courses = new List<Course>();
return;
}
instructorToUpdate.Courses = instructorToUpdate.Courses ?? new List<Course>();
var parsedIds = selectedCoursesIds.Select(int.Parse);
var instructorCoursesIds = instructorToUpdate.Courses.Select(c => c.CourseID).ToList();
var selectedCourses = _universityContext.Courses.Where(c => parsedIds.Contains(c.CourseID));
// remove courses
foreach (var courseToDelete in instructorCoursesIds.Where(courseId => !selectedCourses.Any(c => c.CourseID == courseId)))
{
instructorToUpdate.Courses.Remove(instructorToUpdate.Courses.Single(c => c.CourseID == courseToDelete));
}
// add courses
foreach (var course in selectedCourses.Where(c => instructorCoursesIds.All(courseId => c.CourseID != courseId)))
{
instructorToUpdate.Courses.Add(course);
}
}
private void PopulateAssigmentCourseData(Instructor instructor)
{
var instructorCoursesIds = instructor.Courses.Select(c => c.CourseID);
var assignedCourseData = from c in _universityContext.Courses
select
new AssignedCourseData()
{
CourseID = c.CourseID,
Title = c.Title,
Assigned = instructorCoursesIds.Contains(c.CourseID)
};
ViewBag.Courses = assignedCourseData.ToList();
}