是否可以从本地文件(不发送到服务器)连接到服务器?

Is it possible to connect to a server from a local file (not sent to server)?

在我的 Web 应用程序中,我想使用 websocket 连接我的应用程序和服务器中的 html 文件。 (使用 socket.io)

是否可以在本地(例如 file:///../../file.htm)而不是在服务器端打开文件后立即启动套接字连接:http://localhost/?

在像下面这样的简单示例中,这怎么可能?

客户:

  var socket = io(); 
  socket.on('connect', function () { 
  socket.emit('a', 'b', function (data) {
  console.log(data); 
  });
});

服务器:

const app = require('express')();
const http = require('http').Server(app);
const io = require('socket.io')(http);
io.sockets.on('connection', function (socket) {
console.log('socket connected');

socket.on('disconnect', function () {
    console.log('socket disconnected');
});
});
http.listen(80, (ff) =>
console.log('Example app listening on port 80!'));

这是最基本的socket.io服务器:

const io = require('socket.io')(3000);
io.on('connection', function (socket) {
    console.log('client connected');

    socket.on('disconnect', () => {
        console.log('client disconnected');
    });
});

console.log('socket.io server started at port 3000');

和 html 客户端,您可以在浏览器中将其作为文件:///client.html 打开:

<!doctype html>
<html>
  <body>
    <h1>Testing socket.io</h1>
    <h3 id="socket">waiting...</h3>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/2.0.1/socket.io.js"></script>
    <script>
        var socket = io('http://localhost:3000');

        socket.on('connect', function() {
            document.getElementById("socket").innerHTML = "socket connected";
        });

        socket.on('disconnect', function() {
            document.getElementById("socket").innerHTML = "socket disconnected";
        });

    </script>
  </body>
</html>