Swift:按下按钮时执行UITextField

import UIKit

class ViewController: UIViewController {
    var textField: UITextField!
    var button: UIButton!

    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 创建UITextField
        textField = UITextField(frame: CGRect(x: 50, y: 50, width: 200, height: 30))
        textField.placeholder = "请输入文本"
        view.addSubview(textField)
        
        // 创建UIButton
        button = UIButton(type: .system)
        button.frame = CGRect(x: 50, y: 100, width: 100, height: 30)
        button.setTitle("点击", for: .normal)
        button.addTarget(self, action: #selector(buttonTapped), for: .touchUpInside)
        view.addSubview(button)
    }
    
    @objc func buttonTapped() {
        // 获取UITextField的文本内容
        if let text = textField.text {
            // 执行相应的操作，例如打印文本内容
            print("文本内容：\(text)")
        }
    }
}