如何：实现向发现代理注册的可发现的服务

项目
06/10/2024

本主题是讨论如何实现发现代理的四个主题中的第二个主题。在上一主题，如何：实现发现代理中，你实现了发现代理。在本主题中，你将创建一个 WCF 服务，该服务向发现代理发送公告消息（Hello 和 Bye），从而在发现代理中注册和注销该服务。

定义服务协定

将一个新控制台应用程序项目添加到名为 DiscoveryProxyExample 的 Service 解决方案。
添加对下列程序集的引用：
1. System.ServiceModel
2. System.ServiceModel.Discovery
将新类添加到名为 CalculatorService 的项目中。

添加以下 using 指令。

using System;
using System.ServiceModel;

在 CalculatorService.cs 中，定义服务协定。

// Define a service contract.
[ServiceContract(Namespace = "http://Microsoft.Samples.Discovery")]
public interface ICalculatorService
{
    [OperationContract]
    double Add(double n1, double n2);
    [OperationContract]
    double Subtract(double n1, double n2);
    [OperationContract]
    double Multiply(double n1, double n2);
    [OperationContract]
    double Divide(double n1, double n2);
}

同样，在 CalculatorService.cs 中，实现服务协定。

// Service class which implements the service contract.
public class CalculatorService : ICalculatorService
{
    public double Add(double n1, double n2)
    {
        double result = n1 + n2;
        Console.WriteLine("Received Add({0},{1})", n1, n2);
        Console.WriteLine("Return: {0}", result);
        return result;
    }

    public double Subtract(double n1, double n2)
    {
        double result = n1 - n2;
        Console.WriteLine("Received Subtract({0},{1})", n1, n2);
        Console.WriteLine("Return: {0}", result);
        return result;
    }

    public double Multiply(double n1, double n2)
    {
        double result = n1 * n2;
        Console.WriteLine("Received Multiply({0},{1})", n1, n2);
        Console.WriteLine("Return: {0}", result);
        return result;
    }

    public double Divide(double n1, double n2)
    {
        double result = n1 / n2;
        Console.WriteLine("Received Divide({0},{1})", n1, n2);
        Console.WriteLine("Return: {0}", result);
        return result;
    }
}

承载服务

打开在创建项目时生成的 Program.cs 文件。

添加以下 using 指令。

using System;
using System.ServiceModel;
using System.ServiceModel.Description;
using System.ServiceModel.Discovery;

在 Main() 方法中，添加下面的代码：

// Define the base address of the service
Uri baseAddress = new Uri("net.tcp://localhost:9002/CalculatorService/" + Guid.NewGuid().ToString());
// Define the endpoint address where announcement messages will be sent
Uri announcementEndpointAddress = new Uri("net.tcp://localhost:9021/Announcement");

// Create the service host
ServiceHost serviceHost = new ServiceHost(typeof(CalculatorService), baseAddress);
try
{
    // Add a service endpoint
    ServiceEndpoint netTcpEndpoint = serviceHost.AddServiceEndpoint(typeof(ICalculatorService),
        new NetTcpBinding(), string.Empty);

    // Create an announcement endpoint, which points to the Announcement Endpoint hosted by the proxy service.
    AnnouncementEndpoint announcementEndpoint = new AnnouncementEndpoint(new NetTcpBinding(),
        new EndpointAddress(announcementEndpointAddress));

    // Create a ServiceDiscoveryBehavior and add the announcement endpoint
    ServiceDiscoveryBehavior serviceDiscoveryBehavior = new ServiceDiscoveryBehavior();
    serviceDiscoveryBehavior.AnnouncementEndpoints.Add(announcementEndpoint);

    // Add the ServiceDiscoveryBehavior to the service host to make the service discoverable
    serviceHost.Description.Behaviors.Add(serviceDiscoveryBehavior);

    // Start listening for messages
    serviceHost.Open();

    Console.WriteLine("Calculator Service started at {0}", baseAddress);
    Console.WriteLine();
    Console.WriteLine("Press <ENTER> to terminate the service.");
    Console.WriteLine();
    Console.ReadLine();

    serviceHost.Close();
}
catch (CommunicationException e)
{
    Console.WriteLine(e.Message);
}
catch (TimeoutException e)
{
    Console.WriteLine(e.Message);
}

if (serviceHost.State != CommunicationState.Closed)
{
    Console.WriteLine("Aborting the service...");
    serviceHost.Abort();
}

至此您已完成可检测到的服务的实现过程。请继续查看如何：实现使用发现代理查找服务的客户端应用程序。

示例

下面是本主题中使用的代码的完整清单。

// CalculatorService.cs
//----------------------------------------------------------------
// Copyright (c) Microsoft Corporation.  All rights reserved.
//----------------------------------------------------------------

using System;
using System.ServiceModel;

namespace Microsoft.Samples.Discovery
{
    // Define a service contract.
    [ServiceContract(Namespace = "http://Microsoft.Samples.Discovery")]
    public interface ICalculatorService
    {
        [OperationContract]
        double Add(double n1, double n2);
        [OperationContract]
        double Subtract(double n1, double n2);
        [OperationContract]
        double Multiply(double n1, double n2);
        [OperationContract]
        double Divide(double n1, double n2);
    }

    // Service class which implements the service contract.
    public class CalculatorService : ICalculatorService
    {
        public double Add(double n1, double n2)
        {
            double result = n1 + n2;
            Console.WriteLine("Received Add({0},{1})", n1, n2);
            Console.WriteLine("Return: {0}", result);
            return result;
        }

        public double Subtract(double n1, double n2)
        {
            double result = n1 - n2;
            Console.WriteLine("Received Subtract({0},{1})", n1, n2);
            Console.WriteLine("Return: {0}", result);
            return result;
        }

        public double Multiply(double n1, double n2)
        {
            double result = n1 * n2;
            Console.WriteLine("Received Multiply({0},{1})", n1, n2);
            Console.WriteLine("Return: {0}", result);
            return result;
        }

        public double Divide(double n1, double n2)
        {
            double result = n1 / n2;
            Console.WriteLine("Received Divide({0},{1})", n1, n2);
            Console.WriteLine("Return: {0}", result);
            return result;
        }
    }
}

// Program.cs
//----------------------------------------------------------------
// Copyright (c) Microsoft Corporation.  All rights reserved.
//----------------------------------------------------------------

using System;
using System.ServiceModel;
using System.ServiceModel.Description;
using System.ServiceModel.Discovery;

namespace Microsoft.Samples.Discovery
{
    class Program
    {
        public static void Main()
        {
            Uri baseAddress = new Uri("net.tcp://localhost:9002/CalculatorService/" + Guid.NewGuid().ToString());
            Uri announcementEndpointAddress = new Uri("net.tcp://localhost:9021/Announcement");

            ServiceHost serviceHost = new ServiceHost(typeof(CalculatorService), baseAddress);
            try
            {
                ServiceEndpoint netTcpEndpoint = serviceHost.AddServiceEndpoint(typeof(ICalculatorService),
                    new NetTcpBinding(), string.Empty);

                // Create an announcement endpoint, which points to the Announcement Endpoint hosted by the proxy service.
                AnnouncementEndpoint announcementEndpoint = new AnnouncementEndpoint(new NetTcpBinding(),
                    new EndpointAddress(announcementEndpointAddress));

                ServiceDiscoveryBehavior serviceDiscoveryBehavior = new ServiceDiscoveryBehavior();
                serviceDiscoveryBehavior.AnnouncementEndpoints.Add(announcementEndpoint);

                // Make the service discoverable
                serviceHost.Description.Behaviors.Add(serviceDiscoveryBehavior);

                serviceHost.Open();

                Console.WriteLine("Calculator Service started at {0}", baseAddress);
                Console.WriteLine();
                Console.WriteLine("Press <ENTER> to terminate the service.");
                Console.WriteLine();
                Console.ReadLine();

                serviceHost.Close();
            }
            catch (CommunicationException e)
            {
                Console.WriteLine(e.Message);
            }
            catch (TimeoutException e)
            {
                Console.WriteLine(e.Message);
            }

            if (serviceHost.State != CommunicationState.Closed)
            {
                Console.WriteLine("Aborting the service...");
                serviceHost.Abort();
            }
        }
    }
}

通过

如何：实现向发现代理注册的可发现的服务

定义服务协定

承载服务

示例

另请参阅

其他资源