public PatientCategory(Patients patients)
        {
            InitializeComponent();

            patientCategoryViewModel = new PatientCategoryViewModel(patients);

            DataContext = patientCategoryViewModel;
        }
        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            if (dde == null)
            {
                dde = new DigiDentalEntities();
            }

            if (pcvm == null)
            {
                pcvm = new PatientCategoryViewModel();
            }
            DataContext = pcvm;
        }