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Detailed explanation of node.js using websocket based on express

小云云
小云云Original
2017-12-23 09:03:502717browse

This article mainly introduces the method of node.js using websocket based on express. It analyzes the related settings and usage techniques of node.js based on express calling websocket based on the example. Friends who need it can refer to it. I hope it can help everyone.

I also searched for this effect for a long time, and the test was successful. Anyway, it was successful, let’s take a look.

First you need to install the socket.io module


npm install socket.io --save

Then open express's app.js and import the module. Add two lines

# below the


var app = express();

around line 12.


##

var server = require('http').Server(app);
var io = require('socket.io')(server);

Then add


app.use(function(req, res, next){
 res.io = io;
 next();
});

to more than 20 lines. Since I don’t like to start from www, so in app.js Added a few more lines of code to the second to last line at the bottom


var port = 3000;
app.set('port', port);
server.listen(port);

This will start listening to port 3000

In this way, the preparations are complete Completed, and then start the example

Use the official sample code to test, you can write it directly into app.js


io.on('connection', function (socket) {
 socket.emit('news', { hello: 'world1' });
 socket.on('my other event', function (data) {
  console.log(data);
 });
});

The preparation of the server has been completed , first introduce the socket.js file into the client page


<script src=&#39;javascripts/socket.io-1.4.5.js&#39;></script>
var socket = io.connect("//localhost:3000");
socket.on(&#39;news&#39;, function (data) {
  console.log(data);
  alert(data);
  socket.emit(&#39;my other event&#39;, { my: &#39;data&#39; });
});

Then open the page and test it

If you want to send information from the server to only one page , you can write like this

router.get(&#39;/&#39;, function(req, res, next) {
  //只有当前页面可以获得
  res.io.on(&#39;connection&#39;, function(socket) {
    socket.emit(&#39;news&#39;, {
      hello: &#39;world&#39;
    });
    socket.on(&#39;my other event&#39;, function(data) {
      console.log(data);
    });
  });
  //所有页面都可以获得
  var io = require("../app").io;
  io.emit("news",{hello:"myworld"});
  res.render("pclogin.ejs", {});
});

Related recommendations:

About the solution to the problem that the external network of the WebSocket deployment server cannot be connected

About websocket in php Detailed introduction

nodejs+websocket completes a chat system function

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