ServerSocket.js
npm install express@4 socket.io
const express = require('express');
const app = express();
const http = require('http');
const server = http.createServer(app);
const {
Server } = require("socket.io");
const io = new Server(server);
app.get('/', (req, res) => {
res.sendFile(__dirname + '/index.html');
});
io.on('connection', (socket) => {
console.log('a user connected');
socket.on('Hello', (msg) => {
// 向其他人广播，不包含自己
socket.broadcast.emit('Hello', msg);
})
socket.on('chat message', (msg) => {
// 将消息发送给所有人，包括发件人。
io.emit('chat message', msg);
});
socket.on('disconnect', () => {
console.log('user disconnected');
});
});
server.listen(3000, () => {
console.log('listening on *:3000');
});
index.html
<!DOCTYPE html>
<html>
<head>
<title>Socket.IO chat</title>
<style>
body {
margin: 0; padding-bottom: 3rem; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
#form {
background: rgba(0, 0, 0, 0.15); padding: 0.25rem; position: fixed; bottom: 0; left: 0; right: 0; display: flex; height: 3rem; box-sizing: border-box; backdrop-filter: blur(10px); }
#input {
border: none; padding: 0 1rem; flex-grow: 1; border-radius: 2rem; margin: 0.25rem; }
#input:focus {
outline: none; }
#form > button {
background: #333; border: none; padding: 0 1rem; margin: 0.25rem; border-radius: 3px; outline: none; color: #fff; }
#messages {
list-style-type: none; margin: 0; padding: 0; }
#messages > li {
padding: 0.5rem 1rem; }
#messages > li:nth-child(odd) {
background: #efefef; }
</style>
</head>
<body>
<ul id="messages"></ul>
<form id="form" action="">
<input id="input" autocomplete="off" /><button>Send</button>
</form>
<script src="/socket.io/socket.io.js"></script>
<script>
var socket = io();
var messages = document.getElementById('messages');
var form = document.getElementById('form');
var input = document.getElementById('input');
form.addEventListener('submit', function(e) {
e.preventDefault();
if (input.value) {
socket.emit('chat message', input.value);
socket.emit('Hello', input.value);
input.value = '';
}
});
socket.on('Hello', function(msg) {
var item = document.createElement('li');
item.textContent = 'Hello, everyone：' + msg;
messages.appendChild(item);
window.scrollTo(0, document.body.scrollHeight);
});
socket.on('chat message', function(msg) {
var item = document.createElement('li');
item.textContent = msg;
messages.appendChild(item);
window.scrollTo(0, document.body.scrollHeight);
});
</script>
</body>
</html>