Asp.Net SignalR 使用记录

工作上遇到一个推送消息的功能的实现。本着面向百度编程的思想。网上百度了一大堆。主要的实现方式是原生的WebSocket,和SignalR,再次写一个关于Asp.Net SignalR 的demo 

这里简单的介绍一下Signalr,SignalR 封装了WebSocket、ForeverFrame、ServerSentEvents、LongPolling四种主要的传输协议。兼容性比较好,WebSocket 是有要求的,IIS服务需要系统是Win8或者 Server 2012 以上。下面开始撸代码。

1.首先建立一个项目。

2.通过包管理工具,引入SignalR 

3.引入之后,需要手动添加两个类。

PushHub 集线器类,Singlarl类的主要操作都由这个类实现。

    public class PushHub : Hub
    {
        /// <summary>
        /// 第一次连接
        /// </summary>
        /// <returns></returns>
        public override Task OnConnected()
        {
            return base.OnConnected();
        }

        /// <summary>
        /// 断开连接
        /// </summary>
        /// <param name="stopCalled"></param>
        /// <returns></returns>
        public override Task OnDisconnected(bool stopCalled)
        {
            string user = ConnectManager.GetUserName(Context.ConnectionId);
            ConnectManager.RemoveUser(user);
            Show(string.Format("{0}退出", user));

            return base.OnDisconnected(stopCalled);
        }

        /// <summary>
        /// 获取当前的用户标识
        /// </summary>
        /// <returns></returns>
        private string GetUserId()
        {
            return Context.QueryString["userId"];
        }

        /// <summary>
        /// 发送消息
        /// </summary>
        /// <param name="content"></param>
        /// <param name="receiveUser"></param>
        public void Show(string content,string receiveUser="")
        {
            string user = ConnectManager.GetUserName(Context.ConnectionId);
            if (string.IsNullOrEmpty(receiveUser))
            {
                Clients.All.show(content);
            }
            else {
                Clients.Client(ConnectManager.GetUserConnect(receiveUser)).show(string.Format("{0}发消息:{1}",user, content));
            }
            
        }

        /// <summary>
        /// 登录操作
        /// </summary>
        /// <param name="user"></param>
        public void Login(string user)
        {

            ConnectManager.OnlineInit(user, Context.ConnectionId);
            Show(string.Format("{0}:登录成功", user));
        }

    }

4.Startup类

 

    public class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            app.MapSignalR(); //声明注册集线器映射
        }
    }

5.连接管理类

    /// <summary>
    /// 连接管理类
    /// </summary>
    public class ConnectManager
    {
        /// <summary>
        /// 连接记录池
        /// </summary>
        private readonly static ConcurrentDictionary<string, string> _connectPool = new ConcurrentDictionary<string, string>();

        /// <summary>
        /// 添加用户
        /// </summary>
        /// <param name="userKey"></param>
        /// <param name="connection"></param>
        public static void AddUser(string userKey, string connection)
        {
            _connectPool[userKey] = connection;
        }

        /// <summary>
        /// 删除用户
        /// </summary>
        /// <param name="userKey"></param>
        public static void RemoveUser(string userKey)
        {
            string connection = null;
            _connectPool.TryRemove(userKey, out connection);
        }

        /// <summary>
        /// 是否存在连接(是否在线)
        /// </summary>
        /// <param name="receiverId"></param>
        /// <returns></returns>
        public static bool IsOnline(string receiverId)
        {
            return _connectPool.Keys.Contains(receiverId);
        }

        /// <summary>
        /// 推送消息给个人
        /// </summary>
        /// <param name="receiveId"></param>
        /// <param name="msg"></param>
        public static void PushSingleMessage(string receiveId, string msg)
        {
            try
            {
                GetHubContext().Clients.Client(_connectPool[receiveId]).show(msg);
            }
            catch (Exception ex)
            {
                var errMsg = ex.Message;
            }
        }

        /// <summary>
        /// 获取推送上下文
        /// </summary>
        /// <returns></returns>
        public static IHubContext GetHubContext()
        {
            return GlobalHost.ConnectionManager.GetHubContext<PushHub>();
        }

        /// <summary>
        /// 上线初始化
        /// </summary>
        /// <param name="userId">用户ID</param>
        /// <param name="connectionId">连接ID</param>
        public static void OnlineInit(string userId, string connectionId)
        {
            AddUser(userId, connectionId);
        }

        public static string GetUserName(string value)
        {
            return _connectPool.Where(a => a.Value == value).FirstOrDefault().Key;
        }

        public static string GetUserConnect(string userName)
        {
            return _connectPool[userName];
        }
    }

6.前台代码

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title></title>
</head>
<body>
    <div>
        用户名称:<input type="text" id="user" placeholder="输入用户名" class="input" /><input type="button" id="login" value="登录" class="btn btn-sm btn-info" /><br />
        接收人：<input type="text" id="receiveUser" placeholder="接收人(不填默认群发)" class="input" /><br />
        <input type="text" id="content" placeholder="发送内容" class="input" /> &nbsp;&nbsp;<input type="button" value="发送" class="btn btn-sm btn-info" id="send" />
        <div>
            <h4>接收到的信息：</h4>
            <ul id="dataContainer"></ul>
        </div>
    </div>
    <script src="Scripts/jquery-3.3.1.min.js"></script>
    <script src="Scripts/jquery.signalR-2.4.1.min.js"></script>
    <script src="signalr/hubs"></script>  ///这个要注意默认就是这样写,不要问为什么。哈哈
    <script language="javascript">
        $(function () {
            var chat = $.connection.pushHub;
            
            console.log(chat);
            //连接服务端集线器，demoHub为服务端集线器名称，js上首字母须改为小写（系统默认）
            //定义客户端方法，此客户端方法必须与服务端集线器中的方法名称、参数均一致。
            //实际上是服务端调用了前端的js方法（订阅）
            //若多个参数，服务端也需要一致

            chat.client.show = function (content) {
                var html = '<li>' + htmlEncode(content) + "</li>";
                $("#dataContainer").append(html);
            }

            //定义推送
            $.connection.hub.start()
                .done(function () {
                    $("#login").click(function () {
                        chat.server.login($("#user").val());  //将客户端的content内容发送到服务端
                        $("#user").val("");
                    });
                    $("#send").click(function () {
                        chat.server.show($("#content").val(), $("#receiveUser").val());  //将客户端的content内容发送到服务端
                        $("#content").val("");
                    });
                });


        });
        //编码
        function htmlEncode(value) {
            var encodedValue = $('<div />').text(value).html();
            return encodedValue;
        }
    </script>
</body>

</html>

这就是所有的demo的代码

demo代码：https://github.com/chaorending/Demo.SignalR.git