Express-Socket.io连接不起作用

Question

I am a beginner in express and angularjs . I have an express server and I want my web client to connect to: This is the code:

// app.js
var express = require('express');  
var app = express();  
var server = require('http').createServer(app);  
var io = require('socket.io')(server);


var port = 4000;

app.use(express.static('.'));


app.get('/', function (req, res) {
  res.sendFile( './index.html');
});

io.on('connection', function(client) {  
  console.log('Client connected...');

  client.on('join', function(data) {
    console.log(data);
  });

  client.on('join', function(data) {
    console.log(data);
    client.emit('messages', 'Hello from server');
  });


});

server.listen(port, '0.0.0.0');
console.log("App listening on port " + port);

This is the client:

 <script src="/src/bower_components/angular-socket-io/mock/socket-io.js"></script> <script src="/src/bower_components/angular-socket-io/socket.js"></script> <script> var socket = io.connect(); console.log(socket); console.log("socket.io : "); socket.on('connect', function(data) { socket.emit('join', 'Hello World from client'); }); </script> 

I am trying to make it work. But when I reload the webpage, it seems like client don't event try to connect to server. Event if a put wrong address, there is not reaction. Can someone helps me ?

Answer 1

The thing that is preventing the client from sending out that 'join' event to the server is that you don't need to put the socket.emit logic inside of a 'connect' event. After you make your socket on the client side, you are already connected. So try this:

<script src="/src/bower_components/angular-socket-io/mock/socket-io.js"></script>
<script src="/src/bower_components/angular-socket-io/socket.js"></script>
<script>  
  var socket = io.connect();
    console.log(socket);
    console.log("socket.io : ");
    socket.emit('join', 'Hello World from client');
</script>

Also, inside the app.js, it seems that you're subscribing to the 'join' event twice. This is unnecessary, you only need to subscribe to an event once. For example:

io.on('connection', function(client) {  

  client.on('join', function(data) {
    console.log(data);
    client.emit('messages', 'Hello from server');
  });

});