Model binding dynamic collections. III Controller

gistfile1.cs

[HttpPost]
public ActionResult Index(string save, string discard, SortViewModel posted)
{
  if (isSave(save, discard))
  {
      _repository.Save(SortableThing.ToThings(posted.Things));
  }
  IEnumerable<Thing> updatedThings = _repository.Find();
  var model = new SortViewModel
  {
      Things = SortableThing.FromThings(updatedThings)
  };
  return View(model);
}