创建Service Bus可以参照：
https://azure.microsoft.com/en-gb/documentation/articles/service-bus-dotnet-how-to-use-topics-subscriptions/
Azure Service Bus做广播和消息通知功能很合适，并且可以订阅不同的Topic（不同的消息类型或不同的聊天室）。
1. 首先需要安装Azure Service Bus的nuget package：
2. 建议安装Azure Service Explorer来查看Service bus中创建的Q或者Topic（本文主要介绍Topic）https://code.msdn.microsoft.com/windowsazure/Service-Bus-Explorer-f2abca5a很好用，并且开源，可以学习。3. 实现过程3.1 首先创建1个Winform程序，拖两个button和两个Textbox，界面如下：
3.2 创建1个类，叫ChatClient： public class ChatClient{private string ConnStr{get{return CloudConfigurationManager.GetSetting("Microsoft.ServiceBus.ConnectionString");}}private const string topicName = "TestTopic";public OnMsgRecieved OnMsgRecieved;public void Subscribe(string subscriber){var td = new TopicDescription(topicName){MaxSizeInMegabytes = 5120,DefaultMessageTimeToLive = new TimeSpan(0, 1, 0)};// Create a new Topic with custom settingsstring connectionString =CloudConfigurationManager.GetSetting("Microsoft.ServiceBus.ConnectionString");var namespaceManager =NamespaceManager.CreateFromConnectionString(connectionString);if (!namespaceManager.TopicExists(topicName)){namespaceManager.CreateTopic(td);}if (!namespaceManager.SubscriptionExists(topicName, subscriber)){namespaceManager.CreateSubscription(topicName, subscriber);}SubscriptionClient Client = SubscriptionClient.CreateFromConnectionString(ConnStr, topicName, subscriber, ReceiveMode.PeekLock);// Configure the callback optionsOnMessageOptions options = new OnMessageOptions();options.AutoComplete = false;options.AutoRenewTimeout = TimeSpan.FromMinutes(1);Task.Run(() =>{Client.OnMessage((message) =>{try{// Process message from subscriptionOnMsgRecieved(string.Format("{0}:{1}",message.Properties["name"], message.GetBody<string>()));}catch (Exception){// Indicates a problem, unlock message in subscriptionmessage.Abandon();}}, options);});}private TopicClient _topicClient;public TopicClient TopicClient{get{if (_topicClient == null){_topicClient = TopicClient.CreateFromConnectionString(ConnStr, topicName);}return _topicClient;}}public void SendMsg(string name, string msg){var message = new BrokeredMessage(msg);message.Properties["name"] = name;TopicClient.Send(message);}}
1. 代码包含了Subscribe和SendMsg两个方法，注意name用于标识客户端的，如果两个客户端给一样的名字，只有客户端1个客户端能收到消息。
2. 我Hard Code了Topic名称，如果需要实现多种消息广播，给不同的名字就可以了
3. 这行代码：SubscriptionClient Client = SubscriptionClient.CreateFromConnectionString(ConnStr, topicName, subscriber, ReceiveMode.PeekLock);中的ReceiveMode包含两种：PeekLock和ReceiveAndDelete ，前者加锁拿消息放回，后者拿消息并删除。
4. TopicClient不必每次都创建，是支持多线程环境的。
5.var td = new TopicDescription(topicName){MaxSizeInMegabytes = 5120,DefaultMessageTimeToLive = new TimeSpan(0, 1, 0)};这里设置了消息的最大长度和默认生命周期，可根据场景进行配置。Winform的UI逻辑代码相对简单： public partial class Form1 : Form{ChatClient cc = new ChatClient();public Form1(){InitializeComponent();cc.OnMsgRecieved = (msg) =>{SetText(msg);};}private void btnSend_Click(object sender, EventArgs e){cc.SendMsg(txtName.Text, txtMsg.Text);}delegate void SetTextCallback(string text);private void SetText(string text){if (txtResult.InvokeRequired){var d = new SetTextCallback(SetText);Invoke(d, new object[] { text });}else{txtResult.Text += "\r\n" + text;}}private void btnSaveName_Click(object sender, EventArgs e){cc.Subscribe(txtName.Text);}}逻辑很简单，点击SaveName，重新订阅。点Send按钮，发送消息。需要注意的就是跨线程访问UI控件，这里你需要一个delegate。实现截图：
，如果心胸不似海，又怎能有海一样的事业。
