HOW TO：建立需要工作階段的服務

工作階段會在兩個或更多的端點之間建立共用狀態以啟用諸如回呼、多重躍點安全性之類的有用功能，並在用戶端與服務執行個體之間建立關聯。如需詳細資訊 Windows Communication Foundation (WCF) 應用程式中的工作階段詳細資訊，請參閱使用工作階段。

指定合約需要自身繫結來支援工作階段

1. 建立其中至少包含一個作業的服務合約。如需如何建立服務合約的範例，請參閱 HOW TO：定義 Windows Communication Foundation 服務合約。

2. 將 System.ServiceModel.ServiceContractAttribute.SessionMode 屬性設為下列其中一項，以修改宣告合約的 System.ServiceModel.ServiceContractAttribute：

   • System.ServiceModel.SessionMode.Required (如果必須在工作階段內執行合約的話)。

   • System.ServiceModel.SessionMode.Allowed (如果可以在工作階段內執行合約的話)。

   • System.ServiceModel.SessionMode.NotAllowed (如果不得在工作階段內執行合約的話)。

3. 將您的服務端點設定為使用支援工作階段的繫結。下列組態範例說明可支援 WS-ReliableMessaging 工作階段的 System.ServiceModel.WSDualHttpBinding 用法。

   <appSettings>
     <!-- use appSetting to configure base address provided by host -->
     <add key="baseAddress" value="https://localhost:8080/ServiceMetadata" />
   </appSettings>
   <system.serviceModel>
     <services>
       <service 
         name="Microsoft.WCF.Documentation.DuplexHello"
         behaviorConfiguration="mex"
       >
         <endpoint
           address="/DuplexService"
           binding="wsDualHttpBinding"
           contract="Microsoft.WCF.Documentation.IDuplexHello"
          />
         <endpoint
           address=""
           binding="mexHttpBinding"
           contract="IMetadataExchange"
         />
       </service>
     </services>
     <behaviors>
       <serviceBehaviors>
         <behavior name="mex" >
           <serviceMetadata httpGetEnabled="true" />
         </behavior>
       </serviceBehaviors>
     </behaviors>
   </system.serviceModel>
   

範例

下列程式碼範例說明如何指定合約層級的工作階段需求，以及透過組態檔並使用 System.ServiceModel.WSDualHttpBinding 繫結來支援該需求。

Imports System
Imports System.Collections.Generic
Imports System.ServiceModel
Imports System.Threading

Namespace Microsoft.WCF.Documentation
    <ServiceContract(Name:="SampleDuplexHello", Namespace:="http://microsoft.wcf.documentation", _
                     CallbackContract:=GetType(IHelloCallbackContract), SessionMode:=SessionMode.Required)> _
    Public Interface IDuplexHello
        <OperationContract(IsOneWay:=True)> _
        Sub Hello(ByVal greeting As String)
    End Interface

  Public Interface IHelloCallbackContract
    <OperationContract(IsOneWay := True)> _
    Sub Reply(ByVal responseToGreeting As String)
  End Interface

  <ServiceBehaviorAttribute(InstanceContextMode:=InstanceContextMode.PerSession)> _
  Public Class DuplexHello
      Implements IDuplexHello

    Public Sub New()
      Console.WriteLine("Service object created: " & Me.GetHashCode().ToString())
    End Sub

    Protected Overrides Sub Finalize()
      Console.WriteLine("Service object destroyed: " & Me.GetHashCode().ToString())
    End Sub

    Public Sub Hello(ByVal greeting As String) Implements IDuplexHello.Hello
      Console.WriteLine("Caller sent: " & greeting)
      Console.WriteLine("Session ID: " & OperationContext.Current.SessionId)
      Console.WriteLine("Waiting two seconds before returning call.")
      ' Put a slight delay to demonstrate asynchronous behavior on client.
      Thread.Sleep(2000)
      Dim callerProxy As IHelloCallbackContract = OperationContext.Current.GetCallbackChannel(Of IHelloCallbackContract)()
            Dim response = "Service object " & Me.GetHashCode().ToString() & " received: " & greeting
      Console.WriteLine("Sending back: " & response)
      callerProxy.Reply(response)
    End Sub
  End Class
End Namespace

using System;
using System.Collections.Generic;
using System.ServiceModel;
using System.Threading;

namespace Microsoft.WCF.Documentation
{
  [ServiceContract(
    Name = "SampleDuplexHello",
    Namespace = "http://microsoft.wcf.documentation",
    CallbackContract = typeof(IHelloCallbackContract),
    SessionMode = SessionMode.Required
  )]
  public interface IDuplexHello
  {
    [OperationContract(IsOneWay = true)]
    void Hello(string greeting);
  }

  public interface IHelloCallbackContract
  {
    [OperationContract(IsOneWay = true)]
    void Reply(string responseToGreeting);
  }

  [ServiceBehaviorAttribute(InstanceContextMode=InstanceContextMode.PerSession)]
  public class DuplexHello : IDuplexHello
  {

    public DuplexHello()
    {
      Console.WriteLine("Service object created: " + this.GetHashCode().ToString());
    }

    ~DuplexHello()
    {
      Console.WriteLine("Service object destroyed: " + this.GetHashCode().ToString());
    }

    public void Hello(string greeting)
    {
      Console.WriteLine("Caller sent: " + greeting);
      Console.WriteLine("Session ID: " + OperationContext.Current.SessionId);
      Console.WriteLine("Waiting two seconds before returning call.");
      // Put a slight delay to demonstrate asynchronous behavior on client.
      Thread.Sleep(2000);
      IHelloCallbackContract callerProxy
        = OperationContext.Current.GetCallbackChannel<IHelloCallbackContract>();
      string response = "Service object " + this.GetHashCode().ToString() + " received: " + greeting;
      Console.WriteLine("Sending back: " + response);
      callerProxy.Reply(response);
    }
  }
}

<appSettings>
  <!-- use appSetting to configure base address provided by host -->
  <add key="baseAddress" value="https://localhost:8080/ServiceMetadata" />
</appSettings>
<system.serviceModel>
  <services>
    <service 
      name="Microsoft.WCF.Documentation.DuplexHello"
      behaviorConfiguration="mex"
    >
      <endpoint
        address="/DuplexService"
        binding="wsDualHttpBinding"
        contract="Microsoft.WCF.Documentation.IDuplexHello"
       />
      <endpoint
        address=""
        binding="mexHttpBinding"
        contract="IMetadataExchange"
      />
    </service>
  </services>
  <behaviors>
    <serviceBehaviors>
      <behavior name="mex" >
        <serviceMetadata httpGetEnabled="true" />
      </behavior>
    </serviceBehaviors>
  </behaviors>
</system.serviceModel>

另請參閱

參考

System.ServiceModel.ServiceContractAttribute
System.ServiceModel.ServiceContractAttribute.SessionMode
System.ServiceModel.SessionMode