React用socket.io-client的踩坑记录 socket.io-client 版本兼容问题

 useEffect(() => {
    const socket =io(SOCKET_SERVER_URL)
    console.log(socket,'socket')

    socket.on('connect', () => {
      socket.emit('login', uid);
      console.log('连接建立成功了！')
    });
   // 监听来自服务端的消息
    socket.on('new_msg', (msg) => {
      console.log('Received message:', msg);
    });

    socket.on('update_online_count', (onlineCount) => {
      setOnlineUsers(onlineCount);
      console.log(onlineCount,'onlineCount')
    });
    console.log(onlineUsers,'onlineUsers')
    socket.on('disconnect', function () {
      console.log('断开连接了')
    })
    socket.on('connect_error', (error)=>{
      console.log(error.message,'error.message')
    })
    //在组件销毁时断开连接
    return () => {
      socket.disconnect();
    };
  }, [uid]);

 

 但是console.log（server error  error.message)

经过各种尝试才发现和服务端的包版本不兼容 目前版本过高了，降低到"socket.io-client": "^2.3.0",就连接建立成功了！

卸载之前的高版本

npm i socket.io-client@2.3.0就行