文件：app.js

    1. const express = require('express')
    2. const app = express()
    3. const port = 3000
    5. app.get('/', (req, res) => {
    6.   res.send('这是Express响应')
    7. })
    9. app.listen(port, () => {
    10.   console.log(`Example 运行在 ${port} 端口上`)
    11. })
    1. node app.js

    http://localhost:3000/