如何使用Swift代码发送电子邮件背景(macOS)

import MessageUI

class ViewController: UIViewController, MFMailComposeViewControllerDelegate {
    // ...
}

let mailComposeViewController = MFMailComposeViewController()
mailComposeViewController.mailComposeDelegate = self
mailComposeViewController.setSubject("邮件主题")
mailComposeViewController.setToRecipients(["recipient@example.com"])
mailComposeViewController.setCcRecipients(["ccRecipient@example.com"])
mailComposeViewController.setBccRecipients(["bccRecipient@example.com"])
mailComposeViewController.setMessageBody("邮件正文内容", isHTML: false)

if let attachmentData = NSData(contentsOfFile: "文件路径") {
    mailComposeViewController.addAttachmentData(attachmentData as Data, mimeType: "文件类型", fileName: "文件名")
}

if MFMailComposeViewController.canSendMail() {
    self.present(mailComposeViewController, animated: true, completion: nil)
} else {
    // 无法发送电子邮件，显示适当的错误提示
}

func mailComposeController(_ controller: MFMailComposeViewController, didFinishWith result: MFMailComposeResult, error: Error?) {
    switch result {
    case .cancelled:
        // 邮件发送被取消
    case .saved:
        // 邮件被保存到草稿箱
    case .sent:
        // 邮件已成功发送
    case .failed:
        // 邮件发送失败
    default:
        break
    }
    controller.dismiss(animated: true, completion: nil)
}