nodejs+expressjs+ws实现了websocket即时通讯,服务器和客户端互相通信

nodejs代码

// 导入WebSocket模块:

const WebSocket = require('ws');

// 引用Server类:

const WebSocketServer = WebSocket.Server;

// 实例化:

const wss = new WebSocketServer({

  port: 3001

});

wss.on('connection', function (ws) {

  console.log(`ws 已经连接上`);

  ws.on('message', function (message) {

    console.log(`收到客户端的数据: ${message}`);

    ws.send(`服务端接收到数据，给客户端返回数据: ${message}`, (err) => {

      if (err) {

        console.log(`[SERVER] error: ${err}`);

      }

    });

  })

});

2. html代码

      // 打开一个WebSocket:

      var ws = new WebSocket('ws://localhost:3001');

     

      // 响应onmessage事件:

      ws.onmessage = function (msg) { console.log(msg); };

     

      // 给服务器发送一个字符串:

      ws.addEventListener('open', function () {

        let msg = '我是客户端： ' + location.href

          ws.send(msg)

      });

3. 当然  必须提前导入ws模块  npm i ws