尝试从swift中的应用程序发送电子邮件

import UIKit
import MessageUI

class ViewController: UIViewController, MFMailComposeViewControllerDelegate {
    
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    // 使用MFMailComposeViewController发送电子邮件
    func sendEmail() {
        if MFMailComposeViewController.canSendMail() {
            let mailComposeVC = MFMailComposeViewController()
            mailComposeVC.mailComposeDelegate = self
            mailComposeVC.setToRecipients(["recipient@example.com"])
            mailComposeVC.setSubject("邮件主题")
            mailComposeVC.setMessageBody("邮件正文", isHTML: false)
            
            present(mailComposeVC, animated: true, completion: nil)
        } else {
            print("设备不支持发送邮件")
        }
    }
    
    // MFMailComposeViewControllerDelegate回调方法，处理发送邮件的结果
    func mailComposeController(_ controller: MFMailComposeViewController, didFinishWith result: MFMailComposeResult, error: Error?) {
        switch result {
        case .cancelled:
            print("邮件发送取消")
        case .saved:
            print("邮件保存成功")
        case .sent:
            print("邮件发送成功")
        case .failed:
            print("邮件发送失败")
        default:
            break
        }
        controller.dismiss(animated: true, completion: nil)
    }
}