<!DOCTYPE html>
<html lang="en">
<head>


<title>Document</title>
<script src="https://cdn.socket.io/3.1.1/socket.io.min.js"></script>
</head>
<body>
<input type="text" id="input"><button id="btn">send</button>

<ul id="ret"></ul>
<script>

var input = document.querySelector('#input')

var btn = document.querySelector('#btn')
var ret = document.querySelector('#ret')
var socket = io()

btn.addEventListener('click', function () {
socket.emit('chat', input.value)

input.value = ''
        })

socket.on('chat', function (msg) {
var item = document.createElement('li');
item.textContent = msg;
ret.appendChild(item);
        })
</script>
</body>
</html>
const app = require('express')();
const http = require('http').Server(app);
const io = require('socket.io')(http);

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

io.on('connection', (socket) => {
  socket.on('chat', function (msg) {
      io.emit('chat', 'server:' + msg)
  })
});

http.listen(3000, () => {
  console.log('listening on *:3000');
});


前后端通过emit、on完成数据的通信，需要实时数据的前端只需要订阅对应的事件，就可以拿到实时的数据


​

GitHub: ​​https://github.com/wmui​​