如何：在可靠会话内交换消息

项目
04/06/2023

本主题概述了使用系统提供的绑定之一来启用可靠会话所需的步骤。这些绑定支持可靠会话，但默认情况下不支持。可以强制使用代码或在配置文件中以声明方式启用可靠会话。此过程使用客户端和服务配置文件来启用可靠会话，并规定消息按照发送的相同顺序到达。

此过程的关键部分是终结点配置元素包含一个 bindingConfiguration 属性，该属性引用名为 Binding1 的绑定配置。 <binding> 配置元素引用此名称，以通过将 <reliableSession> 元素的 enabled 属性设置为 true 来启用可靠会话。通过将 ordered 属性设置为 true，可为可靠会话指定有序传送保证。

有关此示例的源副本，请参阅 WS 可靠会话。

使用 WSHttpBinding 配置服务以使用可靠会话

为该类型的服务定义服务协定。

[ServiceContract]
public interface ICalculator
{
    [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);
}

在服务类中实现该服务协定。请注意，在服务的实现内部，未指定地址或绑定信息。无需编写代码以从配置文件检索地址或绑定信息。

public class CalculatorService : ICalculator
{
    public double Add(double n1, double n2)
    {
        return n1 + n2;
    }
    public double Subtract(double n1, double n2)
    {
        return n1 - n2;
    }
    public double Multiply(double n1, double n2)
    {
        return n1 * n2;
    }
    public double Divide(double n1, double n2)
    {
        return n1 / n2;
    }
}

创建 Web.config 文件，为使用 WSHttpBinding 的 CalculatorService 配置终结点，启用可靠会话并按顺序传递所需的消息。

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <system.serviceModel>

    <services>
      <service name="Microsoft.ServiceModel.Samples.CalculatorService">

        <!--
             This endpoint is exposed at the base address provided by
             host: http://localhost/servicemodelsamples/service.svc

             Specify wsHttpBinding binding and a binding configuration
             to use
        -->
        <endpoint address=""
                  binding="wsHttpBinding"
                  bindingConfiguration="Binding1"
                  contract="Microsoft.ServiceModel.Samples.ICalculator" />

        <!--
          The mex endpoint is exposed at
          http://localhost/servicemodelsamples/service.svc/mex
        -->
        <endpoint address="mex"
                  binding="mexHttpBinding"
                  contract="IMetadataExchange" />
      </service>
    </services>

    <!--
         Configures WSHttpBinding for reliable sessions with ordered
         delivery.
    -->
    <bindings>
      <wsHttpBinding>
        <binding name="Binding1">
          <reliableSession enabled="true" ordered="true" />
        </binding>
      </wsHttpBinding>
    </bindings>

  </system.serviceModel>
</configuration>

创建包含以下代码行的 Service.svc 文件：

<%@ServiceHost language=c# Service="CalculatorService" %>

将 Service.svc 文件放到 Internet 信息服务 (IIS) 虚拟目录中。

使用 WSHttpBinding 配置客户端以使用可靠会话

从命令行中使用 ServiceModel 元数据实用工具 (Svcutil.exe)，根据服务元数据生成代码：
```
Svcutil.exe <service's Metadata Exchange (MEX) address or HTTP GET address>
```

生成的客户端包含 ICalculator 接口，该接口定义了客户端实现必须满足的服务协定。

//Generated interface defining the ICalculator contract	
[System.ServiceModel.ServiceContractAttribute(
Namespace="http://Microsoft.ServiceModel.Samples",
ConfigurationName="Microsoft.ServiceModel.Samples.ICalculator")]
public interface ICalculator
{
    [System.ServiceModel.OperationContractAttribute(
    Action="http://Microsoft.ServiceModel.Samples/ICalculator/Add",
    ReplyAction="http://Microsoft.ServiceModel.Samples/ICalculator/AddResponse")]
    double Add(double n1, double n2);

    [System.ServiceModel.OperationContractAttribute(
    Action="http://Microsoft.ServiceModel.Samples/ICalculator/Subtract",
    ReplyAction="http://Microsoft.ServiceModel.Samples/ICalculator/SubtractResponse")]
    double Subtract(double n1, double n2);

    [System.ServiceModel.OperationContractAttribute(
    Action="http://Microsoft.ServiceModel.Samples/ICalculator/Multiply",
    ReplyAction="http://Microsoft.ServiceModel.Samples/ICalculator/MultiplyResponse")]
    double Multiply(double n1, double n2);

    [System.ServiceModel.OperationContractAttribute(
    Action="http://Microsoft.ServiceModel.Samples/ICalculator/Divide",
    ReplyAction="http://Microsoft.ServiceModel.Samples/ICalculator/DivideResponse")]
    double Divide(double n1, double n2);
}

生成的客户端应用程序还包含 ClientCalculator 的实现。请注意，在服务的实现内部，未指定地址和绑定信息。无需编写代码以从配置文件检索地址或绑定信息。

// Implementation of the CalculatorClient
public partial class CalculatorClient :
    System.ServiceModel.ClientBase<Microsoft.ServiceModel.Samples.ICalculator>,
    Microsoft.ServiceModel.Samples.ICalculator
{
    public CalculatorClient()
    {
    }

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

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

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

    public CalculatorClient(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);
    }
}

Svcutil.exe 还为使用 WSHttpBinding 类的客户端生成配置。使用 Visual Studio 时，将配置文件命名为 App.config。

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <system.serviceModel>

    <client>
      <!-- 
        Specify wsHttpBinding binding and a binding configuration 
        to use
      -->
      <endpoint 
          address="http://localhost/servicemodelsamples/service.svc" 
          binding="wsHttpBinding" 
          bindingConfiguration="Binding1" 
          contract="Microsoft.ServiceModel.Samples.ICalculator" />
    </client>

    <!-- 
      Configures WSHttpBinding for reliable sessions with ordered 
      delivery
    -->
    <bindings>
      <wsHttpBinding>
        <binding name="Binding1">
          <reliableSession enabled="true" ordered="true" />
        </binding>
      </wsHttpBinding>
    </bindings>

  </system.serviceModel>
</configuration>

在应用程序中创建 ClientCalculator 的实例，然后调用服务操作。

//Client implementation code.
class Client
{
    static void Main()
    {
        // Create a client with given client endpoint configuration
        CalculatorClient client = new CalculatorClient();

        // Call the Add service operation.
        double value1 = 100.00D;
        double value2 = 15.99D;
        double result = client.Add(value1, value2);
        Console.WriteLine("Add({0},{1}) = {2}", value1, value2, result);

        // Call the Subtract service operation.
        value1 = 145.00D;
        value2 = 76.54D;
        result = client.Subtract(value1, value2);
        Console.WriteLine("Subtract({0},{1}) = {2}", value1, value2, result);

        // Call the Multiply service operation.
        value1 = 9.00D;
        value2 = 81.25D;
        result = client.Multiply(value1, value2);
        Console.WriteLine("Multiply({0},{1}) = {2}", value1, value2, result);

        // Call the Divide service operation.
        value1 = 22.00D;
        value2 = 7.00D;
        result = client.Divide(value1, value2);
        Console.WriteLine("Divide({0},{1}) = {2}", value1, value2, result);

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

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

编译并运行客户端。

示例

默认情况下，有多种系统提供的绑定支持可靠会话。其中包括：

有关如何创建支持可靠会话的自定义绑定的示例，请参阅如何使用 HTTPS 创建自定义可靠会话绑定。

另请参阅

可靠会话

如何：在可靠会话内交换消息

使用 WSHttpBinding 配置服务以使用可靠会话

使用 WSHttpBinding 配置客户端以使用可靠会话

示例

另请参阅

其他资源