private void Button_Click_1(object sender, RoutedEventArgs e)  // 注册
        {
            User_register user_Register = new User_register();

            Application.Current.MainWindow = user_Register;
            user_Register.Show();
        }
        private void Button_Click_2(object sender, RoutedEventArgs e)  //编辑
        {
            User_register user_Register = new User_register(util);

            Application.Current.MainWindow = user_Register;
            user_Register.Title            = "修改用户";

            user_Register.IsVisibleChanged += User_Register_IsVisibleChanged;
            user_Register.Show();
        }
        private void Button_Click_1(object sender, RoutedEventArgs e)  //添加
        {
            User_register user_Register = new User_register();

            Application.Current.MainWindow  = user_Register;
            user_Register.IsVisibleChanged += User_Register_IsVisibleChanged;
            user_Register.Show();

            button1.IsEnabled = false;
            button2.IsEnabled = false;
        }