private void MenuItem_Click(object sender, RoutedEventArgs e) { //удалить чат из списка try { if (names.SelectedIndex == -1 || names.SelectedIndex >= names.Items.Count) { return; } var chatClient = new ChatServiceClient(); chatClient.DelSpisok((string)((ListBoxItem)names.Items[names.SelectedIndex]).Content); os.Visibility = Visibility.Hidden; } catch { os.Visibility = Visibility.Visible; } }