如何用按钮UIKit替换textView中的word

import UIKit

class ViewController: UIViewController {
    var textView: UITextView!
    var button: UIButton!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 创建textView
        textView = UITextView(frame: CGRect(x: 20, y: 100, width: 300, height: 200))
        textView.text = "Hello, world! This is a sample text."
        view.addSubview(textView)
        
        // 创建按钮
        button = UIButton(type: UIButton.ButtonType.system)
        button.frame = CGRect(x: 20, y: 350, width: 100, height: 30)
        button.setTitle("Replace", for: .normal)
        button.addTarget(self, action: #selector(buttonTapped), for: .touchUpInside)
        view.addSubview(button)
    }
    
    @objc func buttonTapped() {
        // 替换textView中的word
        let replacedText = textView.text.replacingOccurrences(of: "word", with: button.title(for: .normal) ?? "")
        textView.text = replacedText
    }
}