cannot save changes of courses if remove in edit httppost #1668

Problem when remove course then click submit not save changes although it removed from client side by jquery Details in edit view for every employee i need to do changes by remove or add new courses for employee if i add new courses then click submit button it save what i do but if i remove course from courses then click submit it will not save courses i removed so that i need to check what is wrong in my code my code working without any problem but only have problem i cannot save courses removed in database in employeecourse table when click submit employeecourse table have Id,EmployeeId,CourseId jquery remove client side attached with my question code my code as following

[HttpPost]  
        public ActionResult Edit(EditEmployeeVm model)  
        {  
            var emp = db.Employees.FirstOrDefault(f => f.Id == model.Id);  
            foreach (var couseid in model.CourseIds)  
            {  
                db.EmployeeCourses.Add(new EmployeeCourse { CourseId = couseid, EmployeeId = emp.Id });  
                db.SaveChanges();  
            }  
        
            return View();  
my(custom model) view model using for that  
 public class EditEmployeeVm  
    {  
        public int Id { set; get; }  
        public List<SelectListItem> Courses { get; set; }  
        public int[] CourseIds { set; get; }  
        public List<CourseVm> ExistingCourses { set; get; }  
    }  
    public class CourseVm  
    {  
        public int Id { set; get; }  
        public string Name { set; get; }  
    }  
}

to show what i need clearly see image below link of all project <a class="postlink" href="http://www.dotnetfunda.com/forums/show/21778/cannot-save-changes-of-courses-if-remove-in-edit-httppost">http://www.dotnetfunda.com/forums/show/ ... t-httppost</a>