WebSocket 从入门到实战开发

socket 官网的例子

<script src="/socket.io/socket.io.js"></script>
<script>
  var socket = io();

  var form = document.getElementById('form');
  var input = document.getElementById('input');

  form.addEventListener('submit', function(e) {
    e.preventDefault();
    if (input.value) {
      // 发送消息
      socket.emit('chat message', input.value);
      input.value = '';
    }
  });
  // 接受消息
  socket.on('chat message', function(msg) {
    var item = document.createElement('li');
    item.textContent = msg;
    messages.appendChild(item);
    window.scrollTo(0, document.body.scrollHeight);
  });
</script>

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) => {
  console.log('a user connected');
  socket.on('disconnect', () => {
    console.log('user disconnected');
  });
  // 接受消息
  socket.on('chat message', (msg) => {
    console.log('message: ' + msg);
  });
  // 广播 服务器端发送消息
  socket.broadcast.emit('hi');
  socket.emit('hi');
    
  // 一对一
  socket.to(id).emit('chat message', input.value);
  
  // 断开连接
  socket.on('disconnecting',function(){
  });
});

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

客户端

socket.io-client

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相关资料
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