---

public partial class Form1 : Form
{
    private int dx = 50;
    private int dy = 50;

    public Form1()
    {
        InitializeComponent();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        Rectangle screen = Screen.FromControl(this).WorkingArea;

        int newX = this.Location.X + dx;
        int newY = this.Location.Y + dy;

        if (newX < screen.Left || newX + this.Width > screen.Right)
        {
            dx = -dx;
            newX = this.Location.X + dx;
        }

        if (newY < screen.Top || newY + this.Height > screen.Bottom)
        {
            dy = -dy;
            newY = this.Location.Y + dy;
        }

        this.Location = new Point(newX, newY);

        this.Text = $"X = {this.Location.X}, Y = {this.Location.Y}";
    }
}