Question

socket.emit()可以正常使用回调函数，但是socket.on()不能调用。

socket.on('connect', () => {      
    socket.emit(USER_STATUS_UPDATE, { user, status: 'online' }, console.log(`*********CALL`));

    socket.on(USER_STATUS_UPDATE, (userstatus) => {
          console.debug("USER_STATUS_UPDATE",userstatus);
    };
}

Answer 1

Socket.on在其他方发出套接字消息时触发，而不是在同一方发出套接字消息时触发。

服务器：

const io = require('socket.io')(80);

io.on('connection', function(socket){
  socket.emit('request', /* */); // emit an event to the socket
  io.emit('broadcast', /* */); // emit an event to all connected sockets
  socket.on('reply', function(){ /* */ }); // listen to the event
});

客户：

  const socket = io('http://localhost/');
  socket.on('connect', function () {

    socket.on('request', function (msg) {
      socket.emit('reply', 'hi'); 
    });

    socket.on('broadcast', function (msg) {
      console.log(msg); 
    });

  });

连接上的NodeJS套接字无法正常工作

1 个答案: