public MainWindow() { InitializeComponent(); this.btnPointWay.Click += delegate { using (var ofd = new FolderBrowserDialog()) { if (ofd.ShowDialog() == System.Windows.Forms.DialogResult.OK) { tView.Items.Add(FolderTraversal.CatalogInfo(ofd.SelectedPath)); } } }; this.tView.MouseDoubleClick += delegate { imageView.ItemsSource = FolderTraversal.GetFiles((string)(tView.SelectedItem as TreeViewItem).Tag); }; this.imageView.SelectionChanged += delegate { (imageView.SelectedItem as ImagePair)?.View(); }; }