OperationContextScope Classe

Definizione

public ref class OperationContextScope sealed : IDisposable

public sealed class OperationContextScope : IDisposable

type OperationContextScope = class
    interface IDisposable

Public NotInheritable Class OperationContextScope
Implements IDisposable

Ereditarietà

Object

OperationContextScope

Implementazioni

IDisposable

Esempio

Nell'esempio seguente viene illustrato come utilizzare l'ambito OperationContextScope per creare un nuovo contesto in un'applicazione client per aggiungere un'intestazione personalizzata al messaggio in uscita.

using System;
using System.ServiceModel;
using System.ServiceModel.Channels;
using System.Threading;

public class Client : ISampleServiceCallback
{
  ManualResetEvent wait = null;

  Client()
  {
    this.wait = new ManualResetEvent(false);
  }

  public static void Main()
  {
    Client client = new Client();
    client.Run();
  }

  void Run()
  {
    // Picks up configuration from the config file.
    SampleServiceClient wcfClient = new SampleServiceClient(new InstanceContext(this));
    try
    {
      using (OperationContextScope scope = new OperationContextScope(wcfClient.InnerChannel))
      {
        MessageHeader header
          = MessageHeader.CreateHeader(
          "Service-Bound-CustomHeader",
          "http://Microsoft.WCF.Documentation",
          "Custom Happy Value."
          );
        OperationContext.Current.OutgoingMessageHeaders.Add(header);

        // Making calls.
        Console.WriteLine("Enter the greeting to send: ");
        string greeting = Console.ReadLine();

        //Console.ReadLine();
        header = MessageHeader.CreateHeader(
            "Service-Bound-OneWayHeader",
            "http://Microsoft.WCF.Documentation",
            "Different Happy Value."
          );
        OperationContext.Current.OutgoingMessageHeaders.Add(header);

        // One-way
        wcfClient.Push(greeting);
        this.wait.WaitOne();

        // Done with service.
        wcfClient.Close();
        Console.WriteLine("Done!");
        Console.ReadLine();
      }
    }
    catch (TimeoutException timeProblem)
    {
      Console.WriteLine("The service operation timed out. " + timeProblem.Message);
      Console.ReadLine();
      wcfClient.Abort();
    }
    catch (CommunicationException commProblem)
    {
      Console.WriteLine("There was a communication problem. " + commProblem.Message);
      Console.ReadLine();
      wcfClient.Abort();
    }
  }


  #region ISampleServiceCallback Members

  public void PushBack(string msg)
  {
    Console.WriteLine("Service said: " + msg);
    this.WriteHeaders(OperationContext.Current.IncomingMessageHeaders);
    this.wait.Set();
  }

  void WriteHeaders(MessageHeaders headers)
  {
    Console.ForegroundColor = ConsoleColor.Red;
    Console.WriteLine("IncomingHeader:");
    Console.ForegroundColor = ConsoleColor.Blue;
    foreach (MessageHeaderInfo h in headers)
    {
      if (!h.Actor.Equals(String.Empty))
        Console.WriteLine("\t" + h.Actor);
      Console.ForegroundColor = ConsoleColor.White;
      Console.WriteLine("\t" + h.Name);
      Console.ForegroundColor = ConsoleColor.Blue;
      Console.WriteLine("\t" + h.Namespace);
      Console.WriteLine("\t" + h.Relay);
      if (h.IsReferenceParameter == true)
      {
        Console.WriteLine("IsReferenceParameter header detected: " + h.ToString());
      }
    }
    Console.ResetColor();
  }
  #endregion
}

Imports System.ServiceModel
Imports System.ServiceModel.Channels
Imports System.Threading

Public Class Client
    Implements ISampleServiceCallback
  Private wait As ManualResetEvent = Nothing

  Private Sub New()
    Me.wait = New ManualResetEvent(False)
  End Sub

  Public Shared Sub Main()
    Dim client As New Client()
    client.Run()
  End Sub

  Private Sub Run()
    ' Picks up configuration from the config file.
    Dim wcfClient As New SampleServiceClient(New InstanceContext(Me))
    Try
      Using scope As New OperationContextScope(wcfClient.InnerChannel)
                Dim header As MessageHeader = MessageHeader.CreateHeader("Service-Bound-CustomHeader", _
                                    "http://Microsoft.WCF.Documentation", "Custom Happy Value.")
        OperationContext.Current.OutgoingMessageHeaders.Add(header)

        ' Making calls.
        Console.WriteLine("Enter the greeting to send: ")
        Dim greeting As String = Console.ReadLine()

        'Console.ReadLine();
                header = MessageHeader.CreateHeader("Service-Bound-OneWayHeader", _
                                                    "http://Microsoft.WCF.Documentation", "Different Happy Value.")
        OperationContext.Current.OutgoingMessageHeaders.Add(header)

        ' One-way
        wcfClient.Push(greeting)
        Me.wait.WaitOne()

        ' Done with service. 
        wcfClient.Close()
        Console.WriteLine("Done!")
        Console.ReadLine()
      End Using
    Catch timeProblem As TimeoutException
      Console.WriteLine("The service operation timed out. " & timeProblem.Message)
      Console.ReadLine()
      wcfClient.Abort()
    Catch commProblem As CommunicationException
      Console.WriteLine("There was a communication problem. " & commProblem.Message)
      Console.ReadLine()
      wcfClient.Abort()
    End Try
  End Sub


  #Region "ISampleServiceCallback Members"

  Public Sub PushBack(ByVal msg As String) Implements ISampleServiceCallback.PushBack
    Console.WriteLine("Service said: " & msg)
    Me.WriteHeaders(OperationContext.Current.IncomingMessageHeaders)
    Me.wait.Set()
  End Sub

  Private Sub WriteHeaders(ByVal headers As MessageHeaders)
    Console.ForegroundColor = ConsoleColor.Red
    Console.WriteLine("IncomingHeader:")
    Console.ForegroundColor = ConsoleColor.Blue
    For Each h As MessageHeaderInfo In headers
      If Not h.Actor.Equals(String.Empty) Then
        Console.WriteLine(vbTab & h.Actor)
      End If
      Console.ForegroundColor = ConsoleColor.White
      Console.WriteLine(vbTab & h.Name)
      Console.ForegroundColor = ConsoleColor.Blue
      Console.WriteLine(vbTab & h.Namespace)
      Console.WriteLine(vbTab & h.Relay)
      If h.IsReferenceParameter = True Then
        Console.WriteLine("IsReferenceParameter header detected: " & h.ToString())
      End If
    Next h
    Console.ResetColor()
  End Sub
  #End Region

End Class

Commenti

Utilizzare la classe OperationContextScope per creare l'ambito di un oggetto OperationContext specifico o l'ambito di un nuovo oggetto OperationContext tramite l'oggetto IContextChannel specificato. Un OperationContextScope oggetto può essere usato in un servizio Windows Communication Foundation (WCF) o in un'applicazione client WCF.

Dopo che l'oggetto OperationContextScope ha stabilito il contesto dell'operazione corrente, il contesto OperationContext può essere utilizzato per:

• Accedere e modificare le intestazioni e le altre proprietà dei messaggi in ingresso e in uscita.

• Accedere al runtime, compresi dispatcher, host, canale ed estensioni.

• Accedere agli altri tipi di contesto, ad esempio ai contesti di sicurezza, istanza e richiesta.

• Accedere al canale associato all'oggetto OperationContext o, se il canale implementa l'interfaccia System.ServiceModel.Channels.ISession, all'identificatore di sessione del canale associato.

Quando si crea un ambito OperationContextScope, il contesto OperationContext corrente viene archiviato e il nuovo contesto OperationContext diventa quello restituito dalla proprietà Current. Quando l'ambito OperationContextScope viene eliminato, il contesto originale OperationContext viene ripristinato.

Costruttori

Metodi

Si applica a