服务总线队列入门Get started with Service Bus queues

在本教程中,你将创建 .NET Core 控制台应用程序来向服务总线队列发送消息以及从中接收消息。In this tutorial, you create .NET Core console applications to send messages to and receive messages from a Service Bus queue.

先决条件Prerequisites

  1. Visual Studio 2017 Update 3(版本 15.3 (26730.01))或更高版本。Visual Studio 2017 Update 3 (version 15.3, 26730.01) or later.
  2. NET Core SDK 2.0 或更高版本。NET Core SDK, version 2.0 or later.
  3. Azure 订阅。An Azure subscription. 若要完成本教程,需要一个 Azure 帐户。To complete this tutorial, you need an Azure account. 可以激活 MSDN 订阅者权益或注册试用帐户You can activate your MSDN subscriber benefitsor sign-up for a trial account.
  4. 如果没有可使用的队列,请遵循使用 Azure 门户创建服务总线队列一文来创建队列。If you don't have a queue to work with, follow steps in the Use Azure portal to create a Service Bus queue article to create a queue.
    1. 阅读服务总线队列的快速概述Read the quick overview of Service Bus queues.
    2. 创建一个服务总线命名空间Create a Service Bus namespace.
    3. 获取连接字符串Get the connection string.
    4. 创建一个服务总线队列Create a Service Bus queue.

将消息发送到队列Send messages to the queue

为了将消息发送到队列中,请使用 Visual Studio 编写一个 C# 控制台应用程序。To send messages to the queue, write a C# console application using Visual Studio.

创建控制台应用程序Create a console application

启动 Visual Studio 并创建新的控制台应用 (.NET Core) 项目。Launch Visual Studio and create a new Console App (.NET Core) project.

添加服务总线 NuGet 包Add the Service Bus NuGet package

  1. 右键单击新创建的项目,并选择“管理 NuGet 包” 。Right-click the newly created project and select Manage NuGet Packages.

  2. 单击“浏览”选项卡,搜索 Microsoft.Azure.ServiceBus,然后选择“Microsoft.Azure.ServiceBus”项。Click the Browse tab, search for Microsoft.Azure.ServiceBus, and then select the Microsoft.Azure.ServiceBus item. 单击“安装”以完成安装,并关闭此对话框。Click Install to complete the installation, then close this dialog box.

    选择 NuGet 包

编写将消息发送到队列的代码Write code to send messages to the queue

  1. 在 Program.cs 中将以下 using 语句添加到命名空间定义顶部,位于类声明之前:In Program.cs, add the following using statements at the top of the namespace definition, before the class declaration:

    using System.Text;
    using System.Threading;
    using System.Threading.Tasks;
    using Microsoft.Azure.ServiceBus;
    
  2. Program 类中声明以下变量。Within the Program class, declare the following variables. ServiceBusConnectionString 变量设置为在创建命名空间时获得的连接字符串,并将 QueueName 设置为在创建队列时使用的名称:Set the ServiceBusConnectionString variable to the connection string that you obtained when creating the namespace, and set QueueName to the name that you used when creating the queue:

    const string ServiceBusConnectionString = "<your_connection_string>";
    const string QueueName = "<your_queue_name>";
    static IQueueClient queueClient;
    
  3. Main() 的默认内容替换为以下代码行:Replace the default contents of Main() with the following line of code:

    MainAsync().GetAwaiter().GetResult();
    
  4. Main() 之后直接添加以下异步 MainAsync() 方法,以调用“发送消息”方法:Directly after Main(), add the following asynchronous MainAsync() method that calls the send messages method:

    static async Task MainAsync()
    {
        const int numberOfMessages = 10;
        queueClient = new QueueClient(ServiceBusConnectionString, QueueName);
    
        Console.WriteLine("======================================================");
        Console.WriteLine("Press ENTER key to exit after sending all the messages.");
        Console.WriteLine("======================================================");
    
        // Send messages.
        await SendMessagesAsync(numberOfMessages);
    
        Console.ReadKey();
    
        await queueClient.CloseAsync();
    }
    
  5. MainAsync() 方法后直接添加以下 SendMessagesAsync() 方法,以便执行发送 numberOfMessagesToSend 所指定的消息数(当前设置为 10)的工作:Directly after the MainAsync() method, add the following SendMessagesAsync() method that performs the work of sending the number of messages specified by numberOfMessagesToSend (currently set to 10):

    static async Task SendMessagesAsync(int numberOfMessagesToSend)
    {
        try
        {
            for (var i = 0; i < numberOfMessagesToSend; i++)
            {
                // Create a new message to send to the queue.
                string messageBody = $"Message {i}";
                var message = new Message(Encoding.UTF8.GetBytes(messageBody));
    
                // Write the body of the message to the console.
                Console.WriteLine($"Sending message: {messageBody}");
    
                // Send the message to the queue.
                await queueClient.SendAsync(message);
            }
        }
        catch (Exception exception)
        {
            Console.WriteLine($"{DateTime.Now} :: Exception: {exception.Message}");
        }
    }
    
  6. Program.cs 文件的内容如下所示。Here is what your Program.cs file should look like.

    namespace CoreSenderApp
    {
        using System;
        using System.Text;
        using System.Threading;
        using System.Threading.Tasks;
        using Microsoft.Azure.ServiceBus;
    
        class Program
        {
            // Connection String for the namespace can be obtained from the Azure portal under the 
            // 'Shared Access policies' section.
            const string ServiceBusConnectionString = "<your_connection_string>";
            const string QueueName = "<your_queue_name>";
            static IQueueClient queueClient;
    
            static void Main(string[] args)
            {
                MainAsync().GetAwaiter().GetResult();
            }
    
            static async Task MainAsync()
            {
                const int numberOfMessages = 10;
                queueClient = new QueueClient(ServiceBusConnectionString, QueueName);
    
                Console.WriteLine("======================================================");
                Console.WriteLine("Press ENTER key to exit after sending all the messages.");
                Console.WriteLine("======================================================");
    
                // Send Messages
                await SendMessagesAsync(numberOfMessages);
    
                Console.ReadKey();
    
                await queueClient.CloseAsync();
            }
    
            static async Task SendMessagesAsync(int numberOfMessagesToSend)
            {
                try
                {
                    for (var i = 0; i < numberOfMessagesToSend; i++)
                    {
                        // Create a new message to send to the queue
                        string messageBody = $"Message {i}";
                        var message = new Message(Encoding.UTF8.GetBytes(messageBody));
    
                        // Write the body of the message to the console
                        Console.WriteLine($"Sending message: {messageBody}");
    
                        // Send the message to the queue
                        await queueClient.SendAsync(message);
                    }
                }
                catch (Exception exception)
                {
                    Console.WriteLine($"{DateTime.Now} :: Exception: {exception.Message}");
                }
            }
        }
    }
    
  7. 运行该程序并检查 Azure 门户:在命名空间“概览”窗口中单击队列的名称。Run the program, and check the Azure portal: click the name of your queue in the namespace Overview window. 此时会显示队列的“基本信息”屏幕。The queue Essentials screen is displayed. 请注意,队列的“活动消息计数”值现在为 10Notice that the Active Message Count value for the queue is now 10. 每次运行发件人应用程序而没有检索消息(如下一部分所述)时,该值会增加 10。Each time you run the sender application without retrieving the messages (as described in the next section), this value increases by 10. 另请注意,每次该应用将消息添加到队列,队列的当前大小就会递增,增量为“基本信息”窗口中的“当前”值。Also note that the current size of the queue increments the Current value in the Essentials window each time the app adds messages to the queue.

    消息大小

从队列接收消息Receive messages from the queue

若要接收你发送的消息,请创建另一个 .NET Core 控制台应用程序并安装 Microsoft.Azure.ServiceBus NuGet 包,类似于前面的发件人应用程序。To receive the messages you sent, create another .NET Core console application and install the Microsoft.Azure.ServiceBus NuGet package, similar to the previous sender application.

编写从队列接收消息的代码Write code to receive messages from the queue

  1. 在 Program.cs 中将以下 using 语句添加到命名空间定义顶部,位于类声明之前:In Program.cs, add the following using statements at the top of the namespace definition, before the class declaration:

    using System.Text;
    using System.Threading;
    using System.Threading.Tasks;
    using Microsoft.Azure.ServiceBus;
    
  2. Program 类中声明以下变量。Within the Program class, declare the following variables. ServiceBusConnectionString 变量设置为在创建命名空间时获得的连接字符串,并将 QueueName 设置为在创建队列时使用的名称:Set the ServiceBusConnectionString variable to the connection string that you obtained when creating the namespace, and set QueueName to the name that you used when creating the queue:

    const string ServiceBusConnectionString = "<your_connection_string>";
    const string QueueName = "<your_queue_name>";
    static IQueueClient queueClient;
    
  3. Main() 的默认内容替换为以下代码行:Replace the default contents of Main() with the following line of code:

    MainAsync().GetAwaiter().GetResult();
    
  4. Main() 之后直接添加以下异步 MainAsync() 方法,以调用 RegisterOnMessageHandlerAndReceiveMessages() 方法:Directly after Main(), add the following asynchronous MainAsync() method that calls the RegisterOnMessageHandlerAndReceiveMessages() method:

    static async Task MainAsync()
    {
        queueClient = new QueueClient(ServiceBusConnectionString, QueueName);
    
        Console.WriteLine("======================================================");
        Console.WriteLine("Press ENTER key to exit after receiving all the messages.");
        Console.WriteLine("======================================================");
    
        // Register the queue message handler and receive messages in a loop
        RegisterOnMessageHandlerAndReceiveMessages();
    
        Console.ReadKey();
    
        await queueClient.CloseAsync();
    }
    
  5. MainAsync() 方法后直接添加以下方法,以便注册消息处理程序并接收发件人应用程序发送的消息:Directly after the MainAsync() method, add the following method that registers the message handler and receives the messages sent by the sender application:

    static void RegisterOnMessageHandlerAndReceiveMessages()
    {
        // Configure the message handler options in terms of exception handling, number of concurrent messages to deliver, etc.
        var messageHandlerOptions = new MessageHandlerOptions(ExceptionReceivedHandler)
        {
            // Maximum number of concurrent calls to the callback ProcessMessagesAsync(), set to 1 for simplicity.
            // Set it according to how many messages the application wants to process in parallel.
            MaxConcurrentCalls = 1,
    
            // Indicates whether the message pump should automatically complete the messages after returning from user callback.
            // False below indicates the complete operation is handled by the user callback as in ProcessMessagesAsync().
            AutoComplete = false
        };
    
        // Register the function that processes messages.
        queueClient.RegisterMessageHandler(ProcessMessagesAsync, messageHandlerOptions);
    }
    
  6. 直接在前面的方法后添加以下 ProcessMessagesAsync() 方法,以便处理接收的消息:Directly after the previous method, add the following ProcessMessagesAsync() method to process the received messages:

    static async Task ProcessMessagesAsync(Message message, CancellationToken token)
    {
        // Process the message.
        Console.WriteLine($"Received message: SequenceNumber:{message.SystemProperties.SequenceNumber} Body:{Encoding.UTF8.GetString(message.Body)}");
    
        // Complete the message so that it is not received again.
        // This can be done only if the queue Client is created in ReceiveMode.PeekLock mode (which is the default).
        await queueClient.CompleteAsync(message.SystemProperties.LockToken);
    
        // Note: Use the cancellationToken passed as necessary to determine if the queueClient has already been closed.
        // If queueClient has already been closed, you can choose to not call CompleteAsync() or AbandonAsync() etc.
        // to avoid unnecessary exceptions.
    }
    
  7. 最后,添加以下方法,用于处理可能发生的任何异常:Finally, add the following method to handle any exceptions that might occur:

    // Use this handler to examine the exceptions received on the message pump.
    static Task ExceptionReceivedHandler(ExceptionReceivedEventArgs exceptionReceivedEventArgs)
    {
        Console.WriteLine($"Message handler encountered an exception {exceptionReceivedEventArgs.Exception}.");
        var context = exceptionReceivedEventArgs.ExceptionReceivedContext;
        Console.WriteLine("Exception context for troubleshooting:");
        Console.WriteLine($"- Endpoint: {context.Endpoint}");
        Console.WriteLine($"- Entity Path: {context.EntityPath}");
        Console.WriteLine($"- Executing Action: {context.Action}");
        return Task.CompletedTask;
    }    
    
  8. Program.cs 文件的内容如下所示:Here is what your Program.cs file should look like:

    namespace CoreReceiverApp
    {
        using System;
        using System.Text;
        using System.Threading;
        using System.Threading.Tasks;
        using Microsoft.Azure.ServiceBus;
    
        class Program
        {
            // Connection String for the namespace can be obtained from the Azure portal under the 
            // 'Shared Access policies' section.
            const string ServiceBusConnectionString = "<your_connection_string>";
            const string QueueName = "<your_queue_name>";
            static IQueueClient queueClient;
    
            static void Main(string[] args)
            {
                MainAsync().GetAwaiter().GetResult();
            }
    
            static async Task MainAsync()
            {
                queueClient = new QueueClient(ServiceBusConnectionString, QueueName);
    
                Console.WriteLine("======================================================");
                Console.WriteLine("Press ENTER key to exit after receiving all the messages.");
                Console.WriteLine("======================================================");
    
                // Register QueueClient's MessageHandler and receive messages in a loop
                RegisterOnMessageHandlerAndReceiveMessages();
    
                Console.ReadKey();
    
                await queueClient.CloseAsync();
            }
    
            static void RegisterOnMessageHandlerAndReceiveMessages()
            {
                // Configure the MessageHandler Options in terms of exception handling, number of concurrent messages to deliver etc.
                var messageHandlerOptions = new MessageHandlerOptions(ExceptionReceivedHandler)
                {
                    // Maximum number of Concurrent calls to the callback `ProcessMessagesAsync`, set to 1 for simplicity.
                    // Set it according to how many messages the application wants to process in parallel.
                    MaxConcurrentCalls = 1,
    
                    // Indicates whether MessagePump should automatically complete the messages after returning from User Callback.
                    // False below indicates the Complete will be handled by the User Callback as in `ProcessMessagesAsync` below.
                    AutoComplete = false
                };
    
                // Register the function that will process messages
                queueClient.RegisterMessageHandler(ProcessMessagesAsync, messageHandlerOptions);
            }
    
            static async Task ProcessMessagesAsync(Message message, CancellationToken token)
            {
                // Process the message
                Console.WriteLine($"Received message: SequenceNumber:{message.SystemProperties.SequenceNumber} Body:{Encoding.UTF8.GetString(message.Body)}");
    
                // Complete the message so that it is not received again.
                // This can be done only if the queueClient is created in ReceiveMode.PeekLock mode (which is default).
                await queueClient.CompleteAsync(message.SystemProperties.LockToken);
    
                // Note: Use the cancellationToken passed as necessary to determine if the queueClient has already been closed.
                // If queueClient has already been Closed, you may chose to not call CompleteAsync() or AbandonAsync() etc. calls 
               // to avoid unnecessary exceptions.
            }
    
            static Task ExceptionReceivedHandler(ExceptionReceivedEventArgs exceptionReceivedEventArgs)
            {
                Console.WriteLine($"Message handler encountered an exception {exceptionReceivedEventArgs.Exception}.");
                var context = exceptionReceivedEventArgs.ExceptionReceivedContext;
                Console.WriteLine("Exception context for troubleshooting:");
                Console.WriteLine($"- Endpoint: {context.Endpoint}");
                Console.WriteLine($"- Entity Path: {context.EntityPath}");
                Console.WriteLine($"- Executing Action: {context.Action}");
                return Task.CompletedTask;
            }
        }
    }
    
  9. 运行该程序,并再次检查门户。Run the program, and check the portal again. 请注意,“活动消息计数”和“当前”值现在为 0Notice that the Active Message Count and Current values are now 0.

    队列长度

祝贺!Congratulations! 你现在已创建队列、将一组消息发送到该队列,以及从该队列接收这些消息。You have now created a queue, sent a set of messages to that queue, and received those messages from the same queue.

Note

可以使用服务总线资源管理器管理服务总线资源。You can manage Service Bus resources with Service Bus Explorer. 服务总线资源管理器允许用户连接到服务总线命名空间并以一种简单的方式管理消息传送实体。The Service Bus Explorer allows users to connect to a Service Bus namespace and administer messaging entities in an easy manner. 该工具提供高级功能,如导入/导出功能或用于对主题、队列、订阅、中继服务、通知中心和事件中心进行测试的功能。The tool provides advanced features like import/export functionality or the ability to test topic, queues, subscriptions, relay services, notification hubs and events hubs.

后续步骤Next steps

查看 GitHub 存储库中的示例,了解服务总线消息传送的一些更高级的功能。Check out our GitHub repository with samples that demonstrate some of the more advanced features of Service Bus messaging.