如何：实现使用发现代理查找服务的客户端应用程序

项目
04/07/2023

本主题是讨论如何实现发现代理的三个主题中的第三个。在上一主题如何实现向发现代理注册的可发现服务中，你实现了向发现代理注册自身的 WCF 服务。在本主题中，你将创建一个使用发现代理来查找 WCF 服务的 WCF 客户端。

实现客户端

将一个新控制台应用程序项目添加到名为 DiscoveryProxyExample 的 Client 解决方案。
添加对下列程序集的引用：
1. System.ServiceModel
2. System.ServiceModel.Discovery
将位于此主题底部的 GeneratedClient.cs 添加到该项目。

注意

此文件通常是使用 Svcutil.exe 等工具生成的。此主题中提供的该文件是为了将任务简化。

打开 Program.cs 文件并添加以下方法。此方法使用一个终结点地址，并使用该地址来初始化服务客户端（代理）。

static void InvokeCalculatorService(EndpointAddress endpointAddress)
{
    // Create a client
    CalculatorServiceClient client = new CalculatorServiceClient(new NetTcpBinding(), endpointAddress);
    Console.WriteLine("Invoking CalculatorService at {0}", endpointAddress.Uri);
    Console.WriteLine();

    double value1 = 100.00D;
    double value2 = 15.99D;

    // Call the Add service operation.
    double result = client.Add(value1, value2);
    Console.WriteLine("Add({0},{1}) = {2}", value1, value2, result);

    // Call the Subtract service operation.
    result = client.Subtract(value1, value2);
    Console.WriteLine("Subtract({0},{1}) = {2}", value1, value2, result);

    // Call the Multiply service operation.
    result = client.Multiply(value1, value2);
    Console.WriteLine("Multiply({0},{1}) = {2}", value1, value2, result);

    // Call the Divide service operation.
    result = client.Divide(value1, value2);
    Console.WriteLine("Divide({0},{1}) = {2}", value1, value2, result);
    Console.WriteLine();

    // Closing the client gracefully closes the connection and cleans up resources
    client.Close();
}

将以下代码添加到 Main 方法中。

public static void Main()
{
    // Create a DiscoveryEndpoint that points to the DiscoveryProxy
    Uri probeEndpointAddress = new Uri("net.tcp://localhost:8001/Probe");
    DiscoveryEndpoint discoveryEndpoint = new DiscoveryEndpoint(new NetTcpBinding(), new EndpointAddress(probeEndpointAddress));

    // Create a DiscoveryClient passing in the discovery endpoint
    DiscoveryClient discoveryClient = new DiscoveryClient(discoveryEndpoint);

    Console.WriteLine("Finding ICalculatorService endpoints using the proxy at {0}", probeEndpointAddress);
    Console.WriteLine();

    try
    {
        // Search for services that implement ICalculatorService
        FindResponse findResponse = discoveryClient.Find(new FindCriteria(typeof(ICalculatorService)));

        Console.WriteLine("Found {0} ICalculatorService endpoint(s).", findResponse.Endpoints.Count);
        Console.WriteLine();

        // Check to see if endpoints were found, if so then invoke the service.
        if (findResponse.Endpoints.Count > 0)
        {
            InvokeCalculatorService(findResponse.Endpoints[0].Address);
        }
    }
    catch (TargetInvocationException)
    {
        Console.WriteLine("This client was unable to connect to and query the proxy. Ensure that the proxy is up and running.");
    }

    Console.WriteLine("Press <ENTER> to exit.");
    Console.ReadLine();
}

您已完成客户端应用程序的实现。继续学习如何测试发现代理。

示例

下面是此主题的完整代码清单。

// GeneratedClient.cs
//----------------------------------------------------------------
// Copyright (c) Microsoft Corporation.  All rights reserved.
//----------------------------------------------------------------
//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by a tool.
//     Runtime Version:2.0.50727.1434
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace Microsoft.Samples.Discovery
{
    [System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "4.0.0.0")]
    [System.ServiceModel.ServiceContractAttribute(Namespace = "http://Microsoft.Samples.Discovery", ConfigurationName = "ICalculatorService")]
    public interface ICalculatorService
    {

        [System.ServiceModel.OperationContractAttribute(ProtectionLevel = System.Net.Security.ProtectionLevel.EncryptAndSign, Action = "http://Microsoft.Samples.Discovery/ICalculatorService/Add", ReplyAction = "http://Microsoft.Samples.Discovery/ICalculatorService/AddResponse")]
        double Add(double n1, double n2);

        [System.ServiceModel.OperationContractAttribute(ProtectionLevel = System.Net.Security.ProtectionLevel.EncryptAndSign, Action = "http://Microsoft.Samples.Discovery/ICalculatorService/Subtract", ReplyAction = "http://Microsoft.Samples.Discovery/ICalculatorService/SubtractResponse")]
        double Subtract(double n1, double n2);

        [System.ServiceModel.OperationContractAttribute(ProtectionLevel = System.Net.Security.ProtectionLevel.EncryptAndSign, Action = "http://Microsoft.Samples.Discovery/ICalculatorService/Multiply", ReplyAction = "http://Microsoft.Samples.Discovery/ICalculatorService/MultiplyResponse")]
        double Multiply(double n1, double n2);

        [System.ServiceModel.OperationContractAttribute(ProtectionLevel = System.Net.Security.ProtectionLevel.EncryptAndSign, Action = "http://Microsoft.Samples.Discovery/ICalculatorService/Divide", ReplyAction = "http://Microsoft.Samples.Discovery/ICalculatorService/DivideResponse")]
        double Divide(double n1, double n2);
    }

    [System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "4.0.0.0")]
    public interface ICalculatorServiceChannel : ICalculatorService, System.ServiceModel.IClientChannel
    {
    }

    [System.Diagnostics.DebuggerStepThroughAttribute()]
    [System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "4.0.0.0")]
    public partial class CalculatorServiceClient : System.ServiceModel.ClientBase<ICalculatorService>, ICalculatorService
    {

        public CalculatorServiceClient()
        {
        }

        public CalculatorServiceClient(string endpointConfigurationName) :
            base(endpointConfigurationName)
        {
        }

        public CalculatorServiceClient(string endpointConfigurationName, string remoteAddress) :
            base(endpointConfigurationName, remoteAddress)
        {
        }

        public CalculatorServiceClient(string endpointConfigurationName, System.ServiceModel.EndpointAddress remoteAddress) :
            base(endpointConfigurationName, remoteAddress)
        {
        }

        public CalculatorServiceClient(System.ServiceModel.Channels.Binding binding, System.ServiceModel.EndpointAddress remoteAddress) :
            base(binding, remoteAddress)
        {
        }

        public double Add(double n1, double n2)
        {
            return base.Channel.Add(n1, n2);
        }

        public double Subtract(double n1, double n2)
        {
            return base.Channel.Subtract(n1, n2);
        }

        public double Multiply(double n1, double n2)
        {
            return base.Channel.Multiply(n1, n2);
        }

        public double Divide(double n1, double n2)
        {
            return base.Channel.Divide(n1, n2);
        }
    }
}

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

using System;
using System.Reflection;
using System.ServiceModel;
using System.ServiceModel.Discovery;

namespace Microsoft.Samples.Discovery
{
    class Client
    {
        public static void Main()
        {
            // Create a DiscoveryEndpoint that points to the DiscoveryProxy
            Uri probeEndpointAddress = new Uri("net.tcp://localhost:8001/Probe");
            DiscoveryEndpoint discoveryEndpoint = new DiscoveryEndpoint(new NetTcpBinding(), new EndpointAddress(probeEndpointAddress));

            DiscoveryClient discoveryClient = new DiscoveryClient(discoveryEndpoint);

            Console.WriteLine("Finding ICalculatorService endpoints using the proxy at {0}", probeEndpointAddress);
            Console.WriteLine();

            try
            {
                // Find ICalculatorService endpoints
                FindResponse findResponse = discoveryClient.Find(new FindCriteria(typeof(ICalculatorService)));

                Console.WriteLine("Found {0} ICalculatorService endpoint(s).", findResponse.Endpoints.Count);
                Console.WriteLine();

                // Check to see if endpoints were found, if so then invoke the service.
                if (findResponse.Endpoints.Count > 0)
                {
                    InvokeCalculatorService(findResponse.Endpoints[0].Address);
                }
            }
            catch (TargetInvocationException)
            {
                Console.WriteLine("This client was unable to connect to and query the proxy. Ensure that the proxy is up and running.");
            }

            Console.WriteLine("Press <ENTER> to exit.");
            Console.ReadLine();
        }

        static void InvokeCalculatorService(EndpointAddress endpointAddress)
        {
            // Create a client
            CalculatorServiceClient client = new CalculatorServiceClient(new NetTcpBinding(), endpointAddress);
            Console.WriteLine("Invoking CalculatorService at {0}", endpointAddress.Uri);
            Console.WriteLine();

            double value1 = 100.00D;
            double value2 = 15.99D;

            // Call the Add service operation.
            double result = client.Add(value1, value2);
            Console.WriteLine("Add({0},{1}) = {2}", value1, value2, result);

            // Call the Subtract service operation.
            result = client.Subtract(value1, value2);
            Console.WriteLine("Subtract({0},{1}) = {2}", value1, value2, result);

            // Call the Multiply service operation.
            result = client.Multiply(value1, value2);
            Console.WriteLine("Multiply({0},{1}) = {2}", value1, value2, result);

            // Call the Divide service operation.
            result = client.Divide(value1, value2);
            Console.WriteLine("Divide({0},{1}) = {2}", value1, value2, result);
            Console.WriteLine();

            // Closing the client gracefully closes the connection and cleans up resources
            client.Close();
        }
    }
}

通过

如何：实现使用发现代理查找服务的客户端应用程序

实现客户端

示例

另请参阅

其他资源