public int AddCar(string registrationNumber, int? customerId,int carModelId)
 {
     Car newCar = new Car
     {
         RegistrationNumber = registrationNumber.Replace(" ", "").Trim(),
         CustomerId = customerId,
         CarModelId = carModelId
     };
     db.Cars.InsertOnSubmit(newCar);
     Save();
     return newCar.Id;
 }
 partial void DeleteCar(Car instance);
 partial void UpdateCar(Car instance);
 partial void InsertCar(Car instance);
		private void detach_Cars(Car entity)
		{
			this.SendPropertyChanging();
			entity.CarModel = null;
		}
		private void attach_Cars(Car entity)
		{
			this.SendPropertyChanging();
			entity.CarModel = this;
		}
		private void attach_Cars(Car entity)
		{
			this.SendPropertyChanging();
			entity.Customer = this;
		}
 public ActionResult AddNewCar(string re, int carModelId)
 {
     Car newCar = new Car
     {
         CarModelId = carModelId,
         RegistrationNumber = re.Trim()
     };
     db.Cars.InsertOnSubmit(newCar);
     db.SubmitChanges();
     Session.Remove("car");
     Session.Add("car", newCar);
     return RedirectToAction("Index");
 }