The code creates a Button control programmatically. First, it creates a Button object and sets its width, height, contents, background and foreground and later the Button is added to the LayoutRoot.
private void CreateAButton()
{
Button btn = new Button();
btn.Height = 80;
btn.Width = 150;
btn.Content = "Click ME";
btn.Background = new SolidColorBrush(Colors.Orange);
btn.Foreground = new SolidColorBrush(Colors.Black);
LayoutRoot.Children.Add(btn);
}