ServiceContractAttribute.CallbackContract Properti

Definisi

Ruang nama:

System.ServiceModel

Rakitan:

System.ServiceModel.dll, System.ServiceModel.Primitives.dll

Paket:

System.ServiceModel.Primitives v10.0.652802

Sumber:

ServiceContractAttribute.cs

Mendapatkan atau menetapkan jenis kontrak panggilan balik jika kontraknya adalah kontrak dupleks.

public:
 property Type ^ CallbackContract { Type ^ get(); void set(Type ^ value); };

public Type CallbackContract { get; set; }

member this.CallbackContract : Type with get, set

Public Property CallbackContract As Type

Nilai Properti

Type

Type Yang menunjukkan kontrak panggilan balik. Defaultnya adalah null.

Contoh

Contoh kode berikut menunjukkan layanan yang menentukan kontrak panggilan balik, yang menunjukkan bahwa layanan jenis IDuplexHello harus memiliki koresponden yang menerapkan layanan jenis IHelloCallbackContract. Selain itu, IHelloCallbackContract menerapkan metode panggilan balik satu arah, memungkinkan layanan untuk memanggil klien tanpa menunggu balasan untuk mendukung klien terdistribusi dan berbasis peristiwa.

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);
  }

  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);
    }
  }
}

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

  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 = 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

Keterangan

Tentukan antarmuka dalam CallbackContract properti yang mewakili kontrak berlawanan yang diperlukan dalam pertukaran pesan dua arah (atau dupleks). Ini memungkinkan aplikasi klien untuk mendengarkan panggilan operasi masuk yang dapat dikirim aplikasi layanan sisi server secara independen dari aktivitas klien. Kontrak panggilan balik yang memiliki operasi satu arah mewakili panggilan dari layanan yang dapat ditangani klien.

Nota

Atribut ServiceContractAttribute diabaikan pada kontrak panggilan balik. Untuk mengonfigurasi perilaku runtime objek panggilan balik, gunakan System.ServiceModel.CallbackBehaviorAttribute.