public ActionResult AddWorkGroup(AddWorkGroupModel model)
        {
            var employee  = db.Employees.Find(model.EmployeeId);
            var workGroup = db.WorkGroups.Find(model.WorkGroupId);

            employee.workGroups.Add(workGroup);
            db.SaveChanges();
            return(RedirectToAction("Details", "Employees", new { id = model.EmployeeId }));
        }
        //GET
        public ActionResult AddWorkGroup(int id)
        {
            Employee emp = db.Employees.Find(id);

            AddWorkGroupModel model = new AddWorkGroupModel();

            model.EmployeeId = emp.EmployeeId;
            model.workGroups = db.WorkGroups.ToList();
            ViewBag.Name     = emp.Name;

            return(View(model));
        }