如何通过React.js/Express.js中的用户输入字段向地址发送电子邮件？

import React, { useState } from 'react';

const EmailForm = () => {
  const [recipient, setRecipient] = useState('');
  const [subject, setSubject] = useState('');
  const [content, setContent] = useState('');

  const handleSubmit = (e) => {
    e.preventDefault();
    fetch('/send-email', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({ recipient, subject, content }),
    })
      .then((response) => response.json())
      .then((data) => {
        console.log(data);
      })
      .catch((error) => {
        console.error('Error:', error);
      });
  };

  return (
    <form onSubmit={handleSubmit}>
      <label>
        Recipient:
        <input
          type="email"
          value={recipient}
          onChange={(e) => setRecipient(e.target.value)}
        />
      </label>
      <label>
        Subject:
        <input
          type="text"
          value={subject}
          onChange={(e) => setSubject(e.target.value)}
        />
      </label>
      <label>
        Content:
        <textarea
          value={content}
          onChange={(e) => setContent(e.target.value)}
        />
      </label>
      <button type="submit">Send Email</button>
    </form>
  );
};

export default EmailForm;

const express = require('express');
const nodemailer = require('nodemailer');

const router = express.Router();

router.post('/send-email', (req, res) => {
  const { recipient, subject, content } = req.body;

  const transporter = nodemailer.createTransport({
    host: 'your-smtp-host',
    port: 587,
    secure: false,
    auth: {
      user: 'your-email',
      pass: 'your-password',
    },
  });

  const mailOptions = {
    from: 'your-email',
    to: recipient,
    subject,
    text: content,
  };

  transporter.sendMail(mailOptions, (error, info) => {
    if (error) {
      console.error(error);
      res.status(500).json({ message: 'Failed to send email' });
    } else {
      console.log('Email sent:', info.response);
      res.json({ message: 'Email sent successfully' });
    }
  });
});

module.exports = router;