如何以编程方式确定iPhone界面方向？

import UIKit

class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        // 设置设备方向通知
        NotificationCenter.default.addObserver(self, selector: #selector(deviceOrientationDidChange), name: UIDevice.orientationDidChangeNotification, object: nil)
    }

    @objc func deviceOrientationDidChange() {
        if UIDevice.current.orientation.isPortrait {
            // 竖屏模式
        } else if UIDevice.current.orientation.isLandscape {
            // 横屏模式
        }
    }
}