private void updateSoldier() { Soldier soldier = Obs.Where(s => s.Id == getSoldierUpdated().Id) as Soldier; Obs.Clear(); bl.updateSoldier(getSoldierUpdated()); meneger meneger = bl.GetMeneger(); ObservableCollection <Soldier> newObs = new ObservableCollection <Soldier>(meneger.soldiers); newObs.ToList().ForEach(s => Obs.Add(s)); Close(); }