如何：在可靠会话内交换消息
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。可使用代码以强制方式或在配置文件中以声明方式以启用可靠会话。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，该属性引用一个名为“Binding1”的绑定配置。<binding> 配置元素然后可以引用此名称，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，请参见 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。而且，不必编写代码也可从配置文件中检索该信息。
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 文件以配置 CalculatorService 的终结点，该终结点将 WSHttpBinding 与启用的可靠会话和所需的消息有序传送一起使用。
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
从命令行使用 ServiceModel 元数据实用工具 (Svcutil.exe) 以从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。而且，不必编写代码也可从配置文件中检索该信息。
// 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。在使用 Visual Studio 时，应在 App.config 文件中命名此文件。
<?xml version="1.0" encoding="utf-8" ?> <configuration> <system.serviceModel> <client> <endpoint address="https://localhost/servicemodelsamples/service.svc" <!-- specify wsHttpBinding binding and a binding configuration to use. --> 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。这些绑定包括：
有关如何创建支持可靠会话的自定义绑定的示例，请参见如何：创建使用 HTTPS 的自定义可靠会话绑定。