webSocket前端+nodejs后端简单案例多人在线聊天

一：下面是一个简单的案例，回车发送消息，多人在线聊天

1.前端代码

<!DOCTYPE html>
<html>

<head>
	<meta charset="UTF-8">
	<title>WebSocket Chat</title>
</head>

<body>
	<script type="text/javascript">
		var socket;
		if (!window.WebSocket) {
			window.WebSocket = window.MozWebSocket;
		}
		if (window.WebSocket) {
			socket = new WebSocket("ws://10.22.12.12:8080/ws");
			socket.onmessage = function (event) {
				var ta = document.getElementById('responseText');
				ta.value = ta.value + '\n' + event.data
			};
			socket.onopen = function (event) {
				var ta = document.getElementById('responseText');
				ta.value = "连接开启!";
			};
			socket.onclose = function (event) {
				var ta = document.getElementById('responseText');
				ta.value = ta.value + "连接被关闭";
			};
		} else {
			alert("你的浏览器不支持 WebSocket！");
		}

		function send(message) {
			if (!window.WebSocket) {
				return;
			}
			if (socket.readyState == WebSocket.OPEN) {
				socket.send(message);
			} else {
				alert("连接没有开启.");
			}
		}
    document.onkeydown=function(event){
    var code = event.keyCode;
    if(code ==13){ //这是键盘的enter监听事件
        //绑定焦点，有可能不成功，需要多试试一些标签 
        document.getElementById("mySend").onclick();
        setTimeout(()=>{
          document.getElementById("myInput").value = ''
        },50)
    }
}
	</script>
	<form onsubmit="return false;">
		<h3>WebSocket 聊天室：</h3>
		<textarea id="responseText" style="width: 500px; height: 300px;"></textarea>
		<br>
		<input type="text" id="myInput" name="message" style="width: 300px" value="Hello~~~">
		<input type="button" id="mySend" value="发送消息" onclick="send(this.form.message.value)">
		<input type="button" onclick="javascript:document.getElementById('responseText').value=''" 
			value="清空聊天记录">
	</form>
	<br>
</body>

</html>

2.后端代码

const WebSocket = require('ws');

const server = new WebSocket.Server({ port: 8080 });

server.on('open', function open() {
  console.log('connected');
});

server.on('close', function close() {
  console.log('disconnected');
});

server.on('connection', function connection(ws, req) {
  const ip = req.connection.remoteAddress;
  const port = req.connection.remotePort;
  const clientName = ip + port;

  console.log('%s is connected', clientName)

  // 发送欢迎信息给客户端
  ws.send("Welcome " + clientName);

  ws.on('message', function incoming(message) {
    console.log('received: %s from %s', message, clientName);
    
    // 广播消息给所有客户端
    server.clients.forEach(function each(client) {
      if (client.readyState === WebSocket.OPEN) {
        client.send( clientName + " -> " + message);
      }
    });

  });

});