web-socket学习

websocket是基于tcp协议注册的全双工通信协议，协议名为ws
可以实现服务器端主动推送

客户端注册

	let ws = new WebSocket('ws:localhost:8000');//根据实际的服务器端口来确定
	//注册事件
	//open,close/message/error
	ws.addEventListener('open',handleOpen,false);
	ws.addEventListener('close',handleClose,false);
	ws.addEventListener('message',handleMessage,false);
	ws.addEventListener('error',handleError,false);
	function handleOpen(){
		// 可以做一些初始化操作
		console.log("open");
	}
	function handleClose(){
		console.log("close");
	}
	function handleMessage(msg){
		console.log("收到消息");
		console.log(msg);
	}
	function handleError(){
		console.log("error");
	}
	//响应用户输入或者触发时可以发送
	ws.send(*****)//发送字符串

服务器端注册

需要npm install -S ws

	//server.js
	const ws = require('ws');
	const app = new ws.Socket({
	    port: 8000,
	});
	let clients = [];//用来记录与服务器通信的用户端然后广播出去
	// app需要注册的事件
	// close open connection message error
	app.on('open',handleOpen);
    app.on('close',handleClose);
    app.on('error',handleError);
    app.on('connection',handleConnection);
    let handleOpen = ()=>{
    	console.log("open");
	}
	let handleClose = ()=>{
	    console.log("close");
	}
	let handleError = ()=>{
	    console.log("error");
	}
	let handleConnection=(ws)=>{
	    console.log("connection");
	    clients.push(ws);
	    ws.on('message',handleMessage);
	}
	let handleMessage = (msg)=>{
	    clients.forEach((conn) => { 								
	        conn.send(msg);  //广播
	    })
	    console.log(msg);
	}

node server.js