1. WebSocket服务端与客户端的建立

WebSocket服务端，在node中运行

const WebSocket = require('ws');

var wss = new WebSocket.Server({ port: 8181 });
wss.on('connection', function (ws) {
    console.log('client connected');
  
    ws.on('message', function (data, isBinary) {
        console.log('Message from client ', isBinary?data:data.toString());
    });
});

WebSocket 客户端，在node中运行

var ws = require("ws");
 
var sock = new ws("ws://localhost:8181/");
sock.on("open", function () {
    console.log("connect success !!!!");
    sock.send("HelloWorld");
});
 
sock.on("error", function(err) {
    console.log("error: ", err);
});
 
sock.on("close", function() {
    console.log("close");
});
 
sock.on("message", function(data) {
    console.log(data);
});

WebSocket客户端，在浏览器中运行

var ws = new WebSocket('ws://localhost:8181');
  ws.onopen = function(e){
    console.log("连接服务器成功");
    ws.send("what`s your name?");
  }
  ws.onclose = function(e){
    console.log("服务器关闭");
  }
  ws.onerror = function(){
    console.log("连接出错");
  }
  
  ws.onmessage = function(e){
    let message = "message:" + e.data + "";
    console.log(message);
  }

以上代码保存为client_chrome.js文件，并在html文件中引用，如下：

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>文档标题</title>
<script type="text/javascript" src="client_chrome.js"></script>
</head>
<body>
	<h1>我的第一个HTML页面</h1>
	<p>我的第一个段落。</p>
</body>
</html>

在浏览器中运行以上html文件即可

2. WebSocket发送Json数据

发送Json数据

// 发送Json数据	
var msg = {
		"client":"control",
		"url":"https://www.163.com"
	}
	var s = JSON.stringify(msg);//将Json对象转为字符串
	console.log(s)
	ws.send(s);

接收Json数据

   ws.on("message", function(data, isBinary){
    console.log("get msg: ", data.toString())
    var msg = JSON.parse(data);  // 字符串转Json对象
    console.log("get client:", msg.client);
   });