[C#][Example]TreeView

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            TreeViewItem tvi1 = new TreeViewItem() { Header = "I" };
            TreeViewItem tvi1A = new TreeViewItem() { Header = "IA" };
            TreeViewItem tvi1A1 = new TreeViewItem() { Header = "IA1" };
            TreeViewItem tvi1A2 = new TreeViewItem() { Header = "IA2" };
            TreeViewItem tvi1B = new TreeViewItem() { Header = "IB" };

            tvi1.Items.Add(tvi1A);
            tvi1A.Items.Add(tvi1A1);
            tvi1A.Items.Add(tvi1A2);
            tvi1.Items.Add(tvi1B);

            treeView1.Items.Add(tvi1);
        }