一个最简单的WebSocket hello world demo

原创

Jerry Wang

发布于 2019-03-10 15:23:57

1.4K0

发布于 2019-03-10 15:23:57

服务器端代码不超过42行：

const WSServer = require("./server.js");
var counter = 0;
function createWebsocket() {
 var host = "127.0.0.1";
 var port = "9999";
 var wsServer = WSServer.startServer(host, port);
 console.log("WebSocket server listens to: " + host + ":" + port);
 wsServer.on('open', (data) => {
 console.log('WS Client has connected: ' + data);
 setInterval(function(){ 
 counter++;
 WSServer.broadcast("Jerry: " + counter );
 }, 3000);

 });
 wsServer.on('dataWS', (data) => {
 console.log('Receive Data from WebUI : ' + data);
 });
 wsServer.on('disconnect', (data) => {
 console.log('WSServer disconnect:' + data.name);
 });
 wsServer.on('close', (data) => {
 console.log('WSServer close: ' + data.name);
 });
 wsServer.on('end', (data) => {
 console.log('WSServer Close: '+data.name);
 });
 wsServer.on('error', (data) => {
 });
}
createWebsocket();
</pre>

代码第10行创建一个WebSocket服务器，监听在9999端口上：

第15～18行每隔3秒发送一个字符串到浏览器，用一个计数器标识每次发送的请求。

代码里所需的server.js我已经上传到我的Github上了：

https://github.com/i042416/KnowlegeRepository/blob/master/practice/nodejs/server.js

使用nodejs启动这个服务器：

网页端代码：

<html>
<script src="socket.io.dev.js">
</script>
<script>
console.log("1");
 var socket = io('ws://127.0.0.1:9999');
 socket.on('connect', function(){
 console.log("connected!");
 });
 socket.on('event', function(data){
 console.log("event: " + data);
 });
 socket.on('news', function(data){
 console.log("data from server: " + JSON.stringify(data,2,2));
 });
 socket.on('disconnect', function(){
 console.log("disconnect...");
 });
</script>
</html>
</pre>

浏览器端每隔三秒收到服务器推送的消息，打印在console上：