问如何访问代码生成的子元素？

EN

public MainWindow()
{
    InitializeComponent();

    //create a StackPanel
    StackPanel myStackPanel = new StackPanel();
    myStackPanel.Margin = new Thickness(20);
    myStackPanel.Orientation = Orientation.Horizontal;

    //add stackpanel to MainWindow
    this.AddChild(myStackPanel);
    this.SizeToContent = System.Windows.SizeToContent.WidthAndHeight;

    //create an array to loop generated items
    int[] myArray = { 1, 2, 3, 4, 5, 6 };

    foreach (int number in myArray)
    {
        //create a border to hold a label
        Border myBorder = new Border();
        myBorder.Width = myBorder.Height = 100;
        myBorder.Background = Brushes.RoyalBlue;
        myBorder.Margin = new Thickness(5);

        //create the label
        Label myLabel = new Label();
        myLabel.Foreground = Brushes.White;
        myLabel.FontSize = 14;
        myLabel.Content = number;
        myLabel.VerticalAlignment = System.Windows.VerticalAlignment.Center;
        myLabel.HorizontalAlignment = System.Windows.HorizontalAlignment.Center;

        //add label to myBorder
        myBorder.Child = myLabel;

        //add myBorder to myStackPanel
        myStackPanel.Children.Add(myBorder);

        myBorder.MouseDown += new MouseButtonEventHandler(myStackPanel_MouseDown);
    }
}

private void myStackPanel_MouseDown(object sender, MouseButtonEventArgs e)
{
    //add code to get child label and set font to bold
}