使用 Node 和 Express 发送邮件时出错答案

【问题标题】：Error while sending mail with Node and Express使用 Node 和 Express 发送邮件时出错
【发布时间】：2021-01-09 08:58:12
【问题描述】：

我正在尝试使用 nodemailer 在提交 HTML 表单时发送邮件。但是当我按下提交按钮时，它会显示这个错误......

TypeError: sendMail is not a function
    at C:\Users\user\Desktop\project\Internship designs\notchup\server.js:20:3
    at Layer.handle [as handle_request] (C:\Users\user\Desktop\project\Internship designs\notchup\node_modules\express\lib\router\layer.js:95:5)
    at next (C:\Users\user\Desktop\project\Internship designs\notchup\node_modules\express\lib\router\route.js:137:13)
    at Route.dispatch (C:\Users\user\Desktop\project\Internship designs\notchup\node_modules\express\lib\router\route.js:112:3)
    at Layer.handle [as handle_request] (C:\Users\user\Desktop\project\Internship designs\notchup\node_modules\express\lib\router\layer.js:95:5)
    at C:\Users\user\Desktop\project\Internship designs\notchup\node_modules\express\lib\router\index.js:281:22
    at Function.process_params (C:\Users\user\Desktop\project\Internship designs\notchup\node_modules\express\lib\router\index.js:335:12)
    at next (C:\Users\user\Desktop\project\Internship designs\notchup\node_modules\express\lib\router\index.js:275:10)
    at jsonParser (C:\Users\user\Desktop\project\Internship designs\notchup\node_modules\body-parser\lib\types\json.js:101:7)
    at Layer.handle [as handle_request] (C:\Users\user\Desktop\project\Internship designs\notchup\node_modules\express\lib\router\layer.js:95:5)

我只收到一封没有任何主题和正文的空白邮件。我尝试更改函数名称，以免它与内置函数冲突。我还尝试将其数据类型从“const”更改为“function”。但这无济于事。我该如何解决这个问题？

index.html

<!DOCTYPE html>
<html lang="en" dir="ltr">
  <head>
    <meta charset="utf-8">
    <title></title>
  </head>
  <body>
    <form class="">
      <input type="text" id="subject" placeholder="Subject"><br>
      <input type="email" id="email" placeholder="Email"><br>
      <textarea name="text" id="text" rows="10" cols="30"></textarea><br>
      <input type="submit" value="Submit">

    </form>

    <!-- JQuery -->
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>

    <!-- CUSTOM script -->
    <script>
        $('form').on('submit', (e) => {
          e.preventDefault();

          const email = $('#email').val().trim();
          const subject = $('#subject').val().trim();
          const text = $('#text').val().trim();

          const data = {
            email,
            subject,
            text
          };

          $.post('/email',data, function() {
            console.log('Server received our data');
          });

        });
    </script>
  </body>
</html>

server.js

const express = require('express');
const sendMail = require('./send-mail');
const app = express();
const path = require('path');

const PORT = 8080;

// Data Parsing
app.use(express.urlencoded({
  extended: false
}));
app.use(express.json());

app.post('/email', (req, res) => {
  // TODO
  // send email here
  const { subject, email, text } = req.body;
  console.log('Data: ', req.body);

  sendMail(email, subject, text, function(err, data) {
    if (err) {
      res.status(500).json({ message: 'Internal Error' });
    } else {
      res.json({ message: 'Email sent!!!' });
    }
  });
  res.json({ message: 'Message received!!!' })
});

app.get('/', (req, res) => {
  res.sendFile(path.join(__dirname, 'views', 'index.html'));
});

app.listen(PORT, () => console.log('Server is starting on PORT, ', 8080));

发送邮件.js

var nodemailer = require('nodemailer');

var transporter = nodemailer.createTransport({
  service: 'gmail',
  auth: {
    user: 'saxena1975sanjeev@gmail.com',
    pass: 'my_password'
  }
});

const sendMail = (email, subject, text) => {
  const mailOptions = {
    from: email,
    to: 'saxena1975sanjeev@gmail.com',
    subject: subject,
    text: text
  };

  transporter.sendMail(mailOptions, function(error, info) {
    if(error) {
      console.log(error);
    } else {
      console.log('Email sent: ' + info.response);
    }
  });
}

module.exports = sendMail();

【问题讨论】：

标签： javascript node.js typescript express mean

【解决方案1】：

错误消息说sendMail 不是函数。因此，您需要查看并确定它是什么。

你在这里给它赋值：

const sendMail = require('./send-mail');

因此查看该文件并查看它是否导出：

module.exports = sendMail();

要为export 设置值，您需要调用 sendMail 并分配其返回值。

其中没有return 语句，所以它返回undefined。

如果要导出sendMail 函数，请导出函数本身。不要附加() 来调用它并获取它的返回值。

【讨论】：

【解决方案2】：

您正在导出 sendMail 的返回值而不是函数本身：

module.exports = sendMail();

改成：

module.exports = sendMail;

【讨论】：

【解决方案3】：

在 send-mail.js 中，不执行 sendMail 函数，只发送函数的引用。

var nodemailer = require('nodemailer');

var transporter = nodemailer.createTransport({
  service: 'gmail',
  auth: {
    user: 'saxena1975sanjeev@gmail.com',
    pass: 'my_password'
  }
});

const sendMail = (email, subject, text) => {
  const mailOptions = {
    from: email,
    to: 'saxena1975sanjeev@gmail.com',
    subject: subject,
    text: text
  };

  transporter.sendMail(mailOptions, function(error, info) {
    if(error) {
      console.log(error);
    } else {
      console.log('Email sent: ' + info.response);
    }
  });
}

module.exports = sendMail; // don't sendMail()

【讨论】：