CallbackBehaviorAttribute.UseSynchronizationContext 属性

定义

命名空间:

System.ServiceModel

程序集:

System.ServiceModel.Duplex.dll

程序集:

System.ServiceModel.dll

获取或设置一个值，该值指定是否使用当前同步上下文来选择执行的线程。

public:
 property bool UseSynchronizationContext { bool get(); void set(bool value); };

public bool UseSynchronizationContext { get; set; }

member this.UseSynchronizationContext : bool with get, set

Public Property UseSynchronizationContext As Boolean

属性值

Boolean

如果对服务的所有调用都必须在 SynchronizationContext 指定的线程上运行，则为 true；否则为 false。 默认值是 true。

示例

下面的代码示例演示了回调对象上的 CallbackBehaviorAttribute，它使用 SynchronizationContext 对象确定要封送到的线程，使用 ValidateMustUnderstand 属性强制执行消息验证，并使用 IncludeExceptionDetailInFaults 属性将异常作为 FaultException 对象返回给服务以便进行调试。

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

namespace Microsoft.WCF.Documentation
{
  [CallbackBehaviorAttribute(
   IncludeExceptionDetailInFaults= true,
    UseSynchronizationContext=true,
    ValidateMustUnderstand=true
  )]
  public class Client : SampleDuplexHelloCallback
  {
    AutoResetEvent waitHandle;

    public Client()
    {
      waitHandle = new AutoResetEvent(false);
    }

    public void Run()
    {
      // Picks up configuration from the configuration file.
      SampleDuplexHelloClient wcfClient
        = new SampleDuplexHelloClient(new InstanceContext(this), "WSDualHttpBinding_SampleDuplexHello");
      try
      {
        Console.ForegroundColor = ConsoleColor.White;
        Console.WriteLine("Enter a greeting to send and press ENTER: ");
        Console.Write(">>> ");
        Console.ForegroundColor = ConsoleColor.Green;
        string greeting = Console.ReadLine();
        Console.ForegroundColor = ConsoleColor.White;
        Console.WriteLine("Called service with: \r\n\t" + greeting);
        wcfClient.Hello(greeting);
        Console.WriteLine("Execution passes service call and moves to the WaitHandle.");
        this.waitHandle.WaitOne();
        Console.ForegroundColor = ConsoleColor.Blue;
        Console.WriteLine("Set was called.");
        Console.Write("Press ");
        Console.ForegroundColor = ConsoleColor.Red;
        Console.Write("ENTER");
        Console.ForegroundColor = ConsoleColor.Blue;
        Console.Write(" to exit...");
        Console.ReadLine();
      }
      catch (TimeoutException timeProblem)
      {
        Console.WriteLine("The service operation timed out. " + timeProblem.Message);
        Console.ReadLine();
      }
      catch (CommunicationException commProblem)
      {
        Console.WriteLine("There was a communication problem. " + commProblem.Message);
        Console.ReadLine();
      }
    }
    public static void Main()
    {
      Client client = new Client();
      client.Run();
    }

    public void Reply(string response)
    {
      Console.WriteLine("Received output.");
      Console.WriteLine("\r\n\t" + response);
      this.waitHandle.Set();
    }
  }
}

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

Namespace Microsoft.WCF.Documentation
  <CallbackBehaviorAttribute(IncludeExceptionDetailInFaults:= True, UseSynchronizationContext:=True, ValidateMustUnderstand:=True)> _
  Public Class Client
      Implements SampleDuplexHelloCallback
    Private waitHandle As AutoResetEvent

    Public Sub New()
      waitHandle = New AutoResetEvent(False)
    End Sub

    Public Sub Run()
      ' Picks up configuration from the configuration file.
      Dim wcfClient As New SampleDuplexHelloClient(New InstanceContext(Me), "WSDualHttpBinding_SampleDuplexHello")
      Try
        Console.ForegroundColor = ConsoleColor.White
        Console.WriteLine("Enter a greeting to send and press ENTER: ")
        Console.Write(">>> ")
        Console.ForegroundColor = ConsoleColor.Green
        Dim greeting As String = Console.ReadLine()
        Console.ForegroundColor = ConsoleColor.White
        Console.WriteLine("Called service with: " & Constants.vbCrLf & Constants.vbTab & greeting)
        wcfClient.Hello(greeting)
        Console.WriteLine("Execution passes service call and moves to the WaitHandle.")
        Me.waitHandle.WaitOne()
        Console.ForegroundColor = ConsoleColor.Blue
        Console.WriteLine("Set was called.")
        Console.Write("Press ")
        Console.ForegroundColor = ConsoleColor.Red
        Console.Write("ENTER")
        Console.ForegroundColor = ConsoleColor.Blue
        Console.Write(" to exit...")
        Console.ReadLine()
      Catch timeProblem As TimeoutException
        Console.WriteLine("The service operation timed out. " & timeProblem.Message)
        Console.ReadLine()
      Catch commProblem As CommunicationException
        Console.WriteLine("There was a communication problem. " & commProblem.Message)
        Console.ReadLine()
      End Try
    End Sub
    Public Shared Sub Main()
      Dim client As New Client()
      client.Run()
    End Sub

    Public Sub Reply(ByVal response As String) Implements SampleDuplexHelloCallback.Reply
      Console.WriteLine("Received output.")
      Console.WriteLine(Constants.vbCrLf & Constants.vbTab & response)
      Me.waitHandle.Set()
    End Sub
  End Class
End Namespace

注解

使用此属性可以提供某些应用程序所需的用户界面线程关联。 例如，Windows 窗体应用程序可能被注册为单一实例服务对象。 在这种情况下，对该服务的所有调用都必须在 Windows 窗体线程上运行。 默认情况下，UseSynchronizationContext 设置为 true，这会使对该服务的所有调用都同步在用户界面线程上运行。

请注意，当调用 DuplexChannelFactory<TChannel>.CreateChannel 或 DuplexClientBase<TChannel>.CreateChannel 时，所使用的线程为当前同步线程。 如果是 Windows 窗体应用程序，则这意味着这些调用应该在调用 Application.Run 方法之后发生。