在winform应用程序中单击按钮后,如何将焦点返回到上次使用的控件？

public partial class Form1 : Form
{
    private Control _lastFocusedControl;

    public Form1()
    {
        InitializeComponent();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        if (_lastFocusedControl != null)
        {
            _lastFocusedControl.Focus();
        }
    }

    protected override void OnControlEnter(ControlEnterEventArgs e)
    {
        base.OnControlEnter(e);
        _lastFocusedControl = e.Control;
    }
}