CallContext 类

定义

public ref class CallContext sealed

[System.Serializable]
public sealed class CallContext

[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class CallContext

[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
[System.Security.SecurityCritical]
public sealed class CallContext

[<System.Serializable>]
type CallContext = class

[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type CallContext = class

[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
[<System.Security.SecurityCritical>]
type CallContext = class

Public NotInheritable Class CallContext

继承

Object

CallContext

属性

SerializableAttribute ComVisibleAttribute SecurityCriticalAttribute

示例

下面的代码示例演示如何使用该 CallContext 类将 主体和标识对象 传输到远程位置进行标识。 若要查看此示例中使用的类的代码 LogicalCallContextData ，请参阅接口的示例 ILogicalThreadAffinative 。 若要查看此示例中使用的类的代码 HelloServiceClass ，请参阅该方法的示例 GetData 。 若要查看此示例中使用的服务器类的代码，请参阅该类的示例 RegisterActivatedServiceType 。

#using <system.dll>
#using <system.runtime.remoting.dll>
#using <service.dll>

using namespace System;
using namespace System::Runtime::Remoting;
using namespace System::Runtime::Remoting::Channels;
using namespace System::Runtime::Remoting::Channels::Tcp;
using namespace System::Runtime::Remoting::Messaging;
using namespace System::Security::Principal;
int main()
{
   GenericIdentity^ ident = gcnew GenericIdentity( "Bob" );
   array<String^>^id = gcnew array<String^>(1);
   id[ 0 ] = "Level1";
   GenericPrincipal^ prpal = gcnew GenericPrincipal( ident,id );
   LogicalCallContextData ^ data = gcnew LogicalCallContextData( prpal );

   //Enter data into the CallContext
   CallContext::SetData( "test data", data );
   Console::WriteLine( data->numOfAccesses );
   ChannelServices::RegisterChannel( gcnew TcpChannel );
   RemotingConfiguration::RegisterActivatedClientType( HelloServiceClass::typeid, "tcp://localhost:8082" );
   HelloServiceClass ^ service = gcnew HelloServiceClass;
   if ( service == nullptr )
   {
      Console::WriteLine( "Could not locate server." );
      return 0;
   }

   // call remote method
   Console::WriteLine();
   Console::WriteLine( "Calling remote Object*" );
   Console::WriteLine( service->HelloMethod( "Caveman" ) );
   Console::WriteLine( service->HelloMethod( "Spaceman" ) );
   Console::WriteLine( service->HelloMethod( "Bob" ) );
   Console::WriteLine( "Finished remote Object* call" );
   Console::WriteLine();

   //Extract the returned data from the call context
   LogicalCallContextData ^ returnedData = static_cast<LogicalCallContextData ^>(CallContext::GetData( "test data" ));
   Console::WriteLine( data->numOfAccesses );
   Console::WriteLine( returnedData->numOfAccesses );
   return 0;
}

using System;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;
using System.Runtime.Remoting.Messaging;
using System.Security.Principal;
using System.Security.Permissions;

public class ClientClass {
   public static void Main() {

      GenericIdentity ident = new GenericIdentity("Bob");
      GenericPrincipal prpal = new GenericPrincipal(ident,
                                                    new string[] {"Level1"});
      LogicalCallContextData data = new LogicalCallContextData(prpal);

      //Enter data into the CallContext
      CallContext.SetData("test data", data);

      Console.WriteLine(data.numOfAccesses);

      ChannelServices.RegisterChannel(new TcpChannel());

      RemotingConfiguration.RegisterActivatedClientType(typeof(HelloServiceClass),
                                                        "tcp://localhost:8082");

      HelloServiceClass service = new HelloServiceClass();

      if(service == null) {
          Console.WriteLine("Could not locate server.");
          return;
      }

      // call remote method
      Console.WriteLine();
      Console.WriteLine("Calling remote object");
      Console.WriteLine(service.HelloMethod("Caveman"));
      Console.WriteLine(service.HelloMethod("Spaceman"));
      Console.WriteLine(service.HelloMethod("Bob"));
      Console.WriteLine("Finished remote object call");
      Console.WriteLine();

      //Extract the returned data from the call context
      LogicalCallContextData returnedData =
         (LogicalCallContextData)CallContext.GetData("test data");

      Console.WriteLine(data.numOfAccesses);
      Console.WriteLine(returnedData.numOfAccesses);
   }
}

Imports System.Runtime.Remoting
Imports System.Runtime.Remoting.Channels
Imports System.Runtime.Remoting.Channels.Tcp
Imports System.Runtime.Remoting.Messaging
Imports System.Security.Principal
Imports System.Security.Permissions


Public Class ClientClass
   <PermissionSet(SecurityAction.LinkDemand)> _
   Public Shared Sub Main()
      
      Dim ident As New GenericIdentity("Bob")
      Dim prpal As New GenericPrincipal(ident, New String() {"Level1"})
      Dim data As New LogicalCallContextData(prpal)
      
      'Enter data into the CallContext
      CallContext.SetData("test data", data)
      
      
      Console.WriteLine(data.numOfAccesses)
      
      ChannelServices.RegisterChannel(New TcpChannel())
      
      RemotingConfiguration.RegisterActivatedClientType(GetType(HelloServiceClass), "tcp://localhost:8082")
      
      Dim service As New HelloServiceClass()
      
      If service Is Nothing Then
         Console.WriteLine("Could not locate server.")
         Return
      End If
      
      
      ' call remote method
      Console.WriteLine()
      Console.WriteLine("Calling remote object")
      Console.WriteLine(service.HelloMethod("Caveman"))
      Console.WriteLine(service.HelloMethod("Spaceman"))
      Console.WriteLine(service.HelloMethod("Bob"))
      Console.WriteLine("Finished remote object call")
      Console.WriteLine()
      
      'Extract the returned data from the call context
      Dim returnedData As LogicalCallContextData = CType(CallContext.GetData("test data"), LogicalCallContextData)
      
      Console.WriteLine(data.numOfAccesses)
      Console.WriteLine(returnedData.numOfAccesses)

   End Sub

End Class

注解

CallContext 是类似于线程本地存储的专用集合对象，用于方法调用，并提供对每个逻辑执行线程唯一的数据槽。 槽不会在其他逻辑线程上的调用上下文之间共享。 对象可以在执行代码路径向下和备份时添加到 CallContext 该对象，并按路径上的各种对象进行检查。

当对另一个 AppDomain对象进行远程方法调用时， CallContext 类将生成一个 LogicalCallContext 随远程调用一起传输的实例。 只有公开ILogicalThreadAffinative接口并存储在接口中的CallContext对象才会在内部LogicalCallContext传播AppDomain。 不支持此接口的对象不会在具有远程方法调用的实例中 LogicalCallContext 传输。

另请参阅

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