SignalR实现服务器与客户端的实时通信

百度百科给它的定义

实现实时通信。什么是实时通信的Web呢？就是让客户端（Web页面）和服务器端可以互相通知消息及调用方法，当然这是实时操作的。

WebSockets是HTML5提供的新的API，可以在Web网页与服务器端间建立Socket连接，当WebSockets可用时（即浏览器支持Html5）SignalR使用WebSockets，当不支持时SignalR将使用其它技术来保证达到相同效果。

SignalR当然也提供了非常简单易用的高阶API，使服务器端可以单个或批量调用客户端上的JavaScript函数，并且非常方便地进行连接管理，例如客户端连接到服务器端，或断开连接，客户端分组，以及客户端授权，使用SignalR都非常容易实现。

它的作用

SignalR 将与客户端进行实时通信带给了ASP .NET 。当然这样既好用，而且也有足够的扩展性。以前用户需要刷新页面或使用Ajax轮询才能实现的实时显示数据，现在只要使用SignalR，就可以简单实现了。最重要的是您无需重新建立项目，使用现有ASP .NET项目即可无缝使用SignalR。

它最强吸引我的地方

应该说，首次听到signalR给我最大的振奋就是它与服务器的实时通信，要知道，以往的十几年里，客户端要想实时与服务器通信，那只有通过长轮询，当AJAX出现之后，这种长轮旬变得漂亮一些，但也终规是轮询，即服务器永远是被动的，客户端你真的很累，呵呵！

实例代码

下面我将以一个非常简单的例子说一个signalR的威力，主要功能是，一个网页，有个登陆，登陆成功后，由服务器去通信客户端，并回调客户端的方法，登出后，同时这样的流程，看一下核心代码：

一首先引用相关DLL

aaarticlea/png;base64,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" alt="" />

二 Startup文件为SignalR的入口

using Microsoft.Owin;

using Owin;

[assembly: OwinStartup(typeof(SignalR.Core.Startup))]

namespace SignalR.Core

{

    public class Startup

    {

        public void Configuration(IAppBuilder app)

        {

            app.MapSignalR();

        }

    }

}

三一组SignalR的JS文件

aaarticlea/png;base64,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" alt="" />

四实现具体业务的核心类文件，它需要集成Hub，需要使用特性HubName为SignalR起个名字，以便在客户端去调用它

using Microsoft.AspNet.SignalR;

using Microsoft.AspNet.SignalR.Hubs;

using SignalR.Core.Model;

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Web;

namespace SignalR.Core

{

    [HubName("UrlHub")]

    public class UrlValid : Hub

    {

        static List<CurrentUser> ConnectedUsers = new List<CurrentUser>();

        public void Connect(string url,string userID)

        {

            var id = Context.ConnectionId;

if (ConnectedUsers.Count(x => x.ConnectionId == id) == )

            {

                ConnectedUsers.Add(new CurrentUser

                {

                    ConnectionId = id,

                    UserID = userID,

                });

                Clients.Caller.onConnected(id, userID, url);

                //Clients.AllExcept(id).onNewUserConnected(id, userID);

                Clients.Client(id).onNewUserConnected(id, userID);

            }

            else

            {

                Clients.Caller.onConnected(id, userID, url);

                Clients.Client(id).onExistUserConnected(id, userID);

                // Clients.AllExcept(id).onExistUserConnected(id, userID);

            }

        }

        /// <summary>

        /// 登出

        /// </summary>

        public void Exit(string userID)

        {

            var id = Context.ConnectionId;

            OnDisconnected();

            Clients.Caller.onConnected(id, userID, "");

            Clients.Client(id).onExit(id, userID);

        }

        /// <summary>

        /// 断开

        /// </summary>

        /// <returns></returns>

        public override System.Threading.Tasks.Task OnDisconnected()

        {

            var item = ConnectedUsers.FirstOrDefault(x => x.ConnectionId == Context.ConnectionId);

            if (item != null)

            {

                ConnectedUsers.Remove(item);

                var id = Context.ConnectionId;

                Clients.All.onUserDisconnected(id, item.UserID);

            }

            return base.OnDisconnected();

        }

    }

}

五核心JS功能代码片断

    <!--Reference the jQuery library. -->

    <script src="/Scripts/jquery-1.8.2.min.js"></script>

    <!--Reference the SignalR library. -->

    <script src="/Scripts/jquery.signalR-1.0.0.js"></script>

    <!--Reference the autogenerated SignalR hub script. -->

    <script src="/signalr/hubs"></script>

    <script type="text/javascript">

        $(function () {

            // Declare a proxy to reference the hub

            var chatHub = $.connection.UrlHub;

            registerClientMethods(chatHub);

            // Start Hub

            $.connection.hub.start().done(function () {

                registerEvents(chatHub);

            });

        });

        //注册客户端事件

        function registerEvents(chatHub) {

            $("#btn").click(function () {

                var url = "dasfjasldfj";

                chatHub.server.connect(url);

            });

            $("#logOut").click(function () {

                chatHub.server.exit();

            });

        }

        //注册客户端方法

        function registerClientMethods(chatHub) {

            chatHub.client.onConnected = function (id, userID, url) {

                console.log("与服务器建立了链接" + url);

            }

            chatHub.client.onUserDisconnected = function (id, userID) {

                console.log("与服务器取消了链接");

            }

            chatHub.client.onNewUserConnected = function (id, userID) {

                alert("新用户完成为合法");

            }

            chatHub.client.onExistUserConnected = function (id, userID) {

                alert("用户" + userID + "不能重复登陆");

            }

            chatHub.client.onExit = function (id, userID) {

                alert("用户" + userID + "成功退出！");

            }

        }

    </script>

OK，现在运行你的程序，就可以实现客户端与服务器端实时通信了，利用这些特性，我们是不是可以实现很多事情呀，让消息推送更可靠吧！