无法让 socket.io 客户端连接到服务器

Question

I am trying to connect a client to a server using express and ran with node.js.

It would seem I am unable to connect to the server. The guide( https://socket.io/get-started/chat ) I followed had the server sending the html page to the client (localhost:3000). I am trying to run the html by double-clicking on a file, but it cannot connect to the running server. I am quite new to this, and any help would be appreciated.

Every 3 or so seconds, this pops up in the browser console:

Error: GET http://file/socket.io/?EIO=3&transport=polling&t=NM2_lBl net::ERR_NAME_NOT_RESOLVED
index.js:83

The index.js file referenced is not written by me., but the line is

Backoff.prototype.setJitter = function(jitter){
  this.jitter = jitter;
};

Here is my code:

My client code is:

var socket = io();
console.log(socket)

function sendMe() {
    socket.emit('data update', me)
}

socket.on('data', function (msg) {
    console.log("test")
    if (msg != null) {
        var real = JSON.parse(msg)
        pUps = real;
    }
});

Any my server code:

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

var characters = [];
var pUps = [];

app.get('/', (req, res) => {
    console.log("Got here")
    res.send('<h1>Hello world</h1>');
});

io.on('connection', (socket) => {
    console.log("connection")
    socket.on('data update', (msg) => {
        //process data
    });
});

http.listen(3000, () => {
    console.log('listening on *:3000');
});

Answer 1

I am trying to run the html by double-clicking on a file, but it cannot connect to the running server.

This will not work. You have to access the HTML file using http:// or https:// , not by opening a local file.