Swift -轻按按钮即可添加和删除UILabel

import UIKit

class ViewController: UIViewController {
    var label: UILabel!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 创建按钮
        let addButton = UIButton(type: .system)
        addButton.setTitle("添加Label", for: .normal)
        addButton.addTarget(self, action: #selector(addLabel), for: .touchUpInside)
        addButton.frame = CGRect(x: 100, y: 100, width: 200, height: 50)
        view.addSubview(addButton)
        
        let removeButton = UIButton(type: .system)
        removeButton.setTitle("删除Label", for: .normal)
        removeButton.addTarget(self, action: #selector(removeLabel), for: .touchUpInside)
        removeButton.frame = CGRect(x: 100, y: 200, width: 200, height: 50)
        view.addSubview(removeButton)
    }
    
    @objc func addLabel() {
        // 创建UILabel
        label = UILabel(frame: CGRect(x: 100, y: 300, width: 200, height: 50))
        label.text = "Hello, World!"
        label.textColor = .black
        label.textAlignment = .center
        view.addSubview(label)
    }
    
    @objc func removeLabel() {
        // 移除UILabel
        label.removeFromSuperview()
    }
}