---

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp2
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void OpenGreeting_Click(object sender, RoutedEventArgs e)
        {
        }

        private void TextBox_TextChanged(object sender, TextChangedEventArgs e)
        {
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            TextBox nameBox = this.Content as TextBox;
            if (nameBox == null)
            {
                Grid mainGrid = this.Content as Grid;
                if (mainGrid != null)
                {
                    foreach (var child in mainGrid.Children)
                    {
                        if (child is TextBox)
                        {
                            nameBox = (TextBox)child;
                            break;
                        }
                    }
                }
            }

            string userName = nameBox != null ? nameBox.Text : "";
            Window1 secondWindow = new Window1(userName);
            secondWindow.Show();
        }
    }
}
//2
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;

namespace WpfApp2
{
    public partial class Window1 : Window
    {
        public Window1(string name)
        {
            InitializeComponent();

            Grid mainGrid = this.Content as Grid;
            if (mainGrid != null)
            {
                foreach (var child in mainGrid.Children)
                {
                    if (child is TextBlock)
                    {
                        TextBlock textBlock = (TextBlock)child;
                        textBlock.Text = $"Привет, {name}!";
                        break;
                    }
                }
            }
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            this.Close();
        }

        private void Button_Click_1(object sender, RoutedEventArgs e)
        {
            MessageBox.Show("Вы нажали 'Спасибо'!");
            this.Close();
        }
    }
}