save courses removed by jquery when click submit button

Question

In edit view When Remove courses by JQUERY and click submit button . changes not saved in database

Detailes

meaning removed course still exist in database after click submit

although it removed by jquery

I try more time to solve this point

i need to check code after else in Edit action

image describe what i need

 

no save to course that removed

code

// remove courses success by jquery
     <script>
            $(function () {
                $(document).on("click", ".remove", function (e) {
                    e.preventDefault();
                    $(this).closest(".course-item").remove();
                });
                $('#AvailableCourses').change(function () {

                    var existingCourses = $("input[name='CourseIds']")
                        .map(function () { return this.value; }).get();
                    }
                });
            });
            </script>

    // here i write code for save courses added or courses removed
    [HttpPost]
            public ActionResult Edit(EditEmployeeVm model)

            {
                var origunalCourseIds = TempData["OriginalId"] as int[];
                var newCourceIds = model.CourseIds;
                foreach (var item in origunalCourseIds)
                {
                    if (newCourceIds.Any(m => m == item))
                    {
    // when add new course then click submit save success in database
                        var emp = db.Employees.FirstOrDefault(f => f.Id == model.Id);
                        foreach (var couseid in newCourceIds)
                        {
                            db.EmployeeCourses.Add(new EmployeeCourse { CourseId = couseid, EmployeeId = emp.Id });
                            db.SaveChanges();

                        }

                    }
                    **else
                    {
    **//remove courses then click submit not save removed item**
                        var emp = db.Employees.FirstOrDefault(f => f.Id == model.Id);
                        foreach (var couseid in newCourceIds)
                        {
                            db.EmployeeCourses.Remove(new EmployeeCourse { CourseId = couseid, EmployeeId = emp.Id });
                            db.EmployeeCourses.Add(new EmployeeCourse { CourseId = couseid, EmployeeId = emp.Id });
                            db.SaveChanges();

                        }


                    }
                }**
                return View();
    }
    //custom model using to my code
    //save in employeecourse table
    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; }
        }
    }
    //in Edit [HTTPGET]  Retrieve courses detailes for employee i need to edit
     public ActionResult Edit(int id)
            {

                var vm = new EditEmployeeVm { Id = id };


                vm.CourseIds = vm.ExistingCourses.Select(g => g.Id).ToArray();
                TempData["OriginalId"] = vm.CourseIds;
                return View(vm);
            }