Procedura: implementare un'applicazione client che usa il proxy di individuazione per cercare un servizio

Articolo
04/10/2024

Quello che segue è il terzo di tre argomenti incentrato sull'implementazione di un proxy di individuazione. Nell'argomento precedente Procedura: Implementare un servizio individuabile che esegue la registrazione con il proxy di individuazione, è stato implementato un servizio WCF che si registra con il proxy di individuazione. In questo argomento verrà creato un client WCF che utilizza il proxy di individuazione per cercare il servizio WCF.

Implementare il client

Aggiungere un nuovo progetto applicazione console denominato DiscoveryProxyExample alla soluzione Client.
Aggiungere riferimenti agli assembly riportati di seguito:
1. System.ServiceModel
2. System.ServiceModel.Discovery
Aggiungere al progetto il file GeneratedClient.cs individuato nella parte inferiore di questo argomento.

Nota

In genere, questo file viene generato utilizzando uno strumento come Svcutil.exe, fornito nel presente argomento per semplificare l'attività.

Aprire il file Program.cs e aggiungere il metodo seguente. Questo metodo prende un indirizzo endpoint e lo utilizza per inizializzare il client del servizio (proxy).

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();
}

Aggiungere il codice seguente al metodo Main.

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();
}

L'implementazione dell'applicazione client è stata completata. Continuare in Procedura: test del proxy di individuazione.

Esempio

Di seguito è riportato il codice completo per questo argomento.

// 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();
        }
    }
}

Procedura: implementare un'applicazione client che usa il proxy di individuazione per cercare un servizio

Implementare il client

Esempio

Vedi anche

Risorse aggiuntive