private void btnAdaug_Click(object sender, RoutedEventArgs e)
        {
            var avn = App.AvionDb;

            RezervareBilet rb = new RezervareBilet();

            rb.IDRezervare = Convert.ToInt32(txtCodRezervare.Text);
            txtCodRezervare.Clear();
            rb.Clasa = txtClasa.Text;
            txtClasa.Clear();
            rb.DataSosire = Convert.ToDateTime(dpDataSosire.Text);
            //dpDataSosire.Clear();
            rb.DataPlecare = Convert.ToDateTime(dpDataPlecare.Text);
            //dpDataPlecare.Clear();
            rb.Destinatie = txtDestinatie.Text;
            txtDestinatie.Clear();
            rb.Tarif = Convert.ToInt32(txtTarif.Text);
            txtTarif.Clear();
            rb.IDPasager = Convert.ToInt32(txtIDPasager.Text);
            txtIDPasager.Clear();

            avn.RezervareBiletes.Add(rb);
            avn.SaveChanges();

            lbRezervareBilet.Items.Clear();

            foreach (var rb1 in avn.RezervareBiletes)
            {
                var itm = new ListViewItem();
                itm.Content = rb1.IDRezervare + " " + rb1.Clasa + " " + rb1.DataSosire + " " + rb1.DataPlecare + " "
                              + rb1.Destinatie + " " + rb1.Tarif + " " + rb.IDPasager + " ";
                itm.Tag = rb1;
                lbRezervareBilet.Items.Add(itm);
            }
        }
        private void btnSterg_Click(object sender, RoutedEventArgs e)
        {
            var avn = App.AvionDb;

            RezervareBilet rb1 = (lbRezervareBilet.SelectedItem as ListViewItem).Tag as RezervareBilet;

            txtSters.Text = " ";
            var s = (from s1 in avn.RezervareBiletes where s1.IDRezervare == rb1.IDRezervare select s1).First();

            avn.RezervareBiletes.Remove(s);
            avn.SaveChanges();
        }
        private void btnModific_Click(object sender, RoutedEventArgs e)
        {
            var avn = App.AvionDb;
            // if(lbClient.SelectedItem!=null)
            RezervareBilet rezbilet = (lbRezervareBilet.SelectedItem as ListViewItem).Tag as RezervareBilet;
            var            rb       = (from rb1 in avn.RezervareBiletes where rezbilet.IDRezervare == rb1.IDRezervare select rb1).First();

            rb.IDRezervare = Convert.ToInt32(txtCodRezervare.Text);
            txtCodRezervare.Clear();
            rb.Clasa = txtClasa.Text;
            txtClasa.Clear();
            rb.DataSosire = Convert.ToDateTime(dpDataSosire.Text);
            //dpDataSosire.Clear();
            rb.DataPlecare = Convert.ToDateTime(dpDataPlecare.Text);
            //dpDataPlecare.Clear();
            rb.Destinatie = txtDestinatie.Text;
            txtDestinatie.Clear();
            rb.Tarif = Convert.ToInt32(txtTarif.Text);
            txtTarif.Clear();
            rb.IDPasager = Convert.ToInt32(txtIDPasager.Text);
            txtIDPasager.Clear();
            avn.SaveChanges();
        }