刚接触C#的时候了解过Socket编程，当时知道可以通过Socket通信实现即时通信，可是做出来类似于飞Q的小东西，但自从做了Web后端之后，对Socket编程渐渐遗忘，前端获取消息通常都是通过轮询的方式定期获取信息，但这种方式并不能达到即时的效果，也会存在大量的资源浪费，最近闲暇时分了解了一下WebSocket，可以通过WebSocket实现即时通信。话不多说，直接上Demo。
Server端（第三方WebSocket库Fleck）：
using Fleck; using System; using System.Collections.Generic; using System.IO; using System.Linq; using System.Text; using System.Threading.Tasks; namespace ConsoleApp6 { class Program { static void Main(string[] args) { FleckLog.Level = LogLevel.Debug; var allSockets = new List<IWebSocketConnection>(); var server = new WebSocketServer("ws://0.0.0.0:7181"); server.Start(socket => { socket.OnOpen = () => { Console.WriteLine("Open!"); allSockets.Add(socket); }; socket.OnClose = () => { Console.WriteLine("Close!"); allSockets.Remove(socket); }; socket.OnMessage = message => { Console.WriteLine(message); allSockets.ToList().ForEach(s => s.Send("Echo: " + message)); }; socket.OnBinary = file => { string path = ("D:/test.txt"); //创建一个文件流 FileStream fs = new FileStream(path, FileMode.Create); //将byte数组写入文件中 fs.Write(file, 0, file.Length); //所有流类型都要关闭流，否则会出现内存泄露问题 fs.Close(); }; }); var input = Console.ReadLine(); while (input != "exit") { foreach (var socket in allSockets.ToList()) { socket.Send(input); } input = Console.ReadLine(); } } } }
JS端
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <html> <head> <title>websocket client</title> <script type="text/javascript"> var start = function () { var inc = document.getElementById('incomming'); var wsImpl = window.WebSocket || window.MozWebSocket; var form = document.getElementById('sendForm'); var input = document.getElementById('sendText'); inc.innerHTML += "connecting to server ..<br/>"; // create a new websocket and connect window.ws = new wsImpl('ws://localhost:7181/'); // when data is comming from the server, this metod is called ws.onmessage = function (evt) { inc.innerHTML += evt.data + '<br/>'; }; // when the connection is established, this method is called ws.onopen = function () { inc.innerHTML += '.. connection open<br/>'; }; // when the connection is closed, this method is called ws.onclose = function () { inc.innerHTML += '.. connection closed<br/>'; } form.addEventListener('submit', function (e) { e.preventDefault(); var val = input.value; ws.send(val); input.value = ""; }); } window.onload = start; </script> </head> <body> <form id="sendForm"> <input id="sendText" placeholder="Text to send" /> </form> <pre id="incomming"></pre> </body> </html>
C#客户端
using System; using System.Net.WebSockets; using System.Text; using System.Threading; namespace ConsoleApp7 { class Program { static void Main(string[] args) { string url = "ws://192.168.4.4:7181"; ClientWebSocket client = new ClientWebSocket(); client.ConnectAsync(new Uri(url), new CancellationToken()).Wait(); try { StartReceiving(client); string line; while ((line = Console.ReadLine()) != "exit") { var array = new ArraySegment<byte>(Encoding.UTF8.GetBytes(line)); client.SendAsync(array, WebSocketMessageType.Text, true, CancellationToken.None); } } catch (Exception ex) { string ss = ex.ToString(); client.CloseAsync(WebSocketCloseStatus.Empty, null, new CancellationToken()).Wait(); } client.CloseAsync(WebSocketCloseStatus.Empty,null, new CancellationToken()).Wait(); } static async void StartReceiving(ClientWebSocket client) { while (true) { var array = new byte[4096]; var result = await client.ReceiveAsync(new ArraySegment<byte>(array), CancellationToken.None); if (result.MessageType == WebSocketMessageType.Text) { string msg = Encoding.UTF8.GetString(array, 0, result.Count); Console.WriteLine("--> {0}", msg); } } } } }