CallContext.GetData(String) Method

Definition

Namespace:

System.Runtime.Remoting.Messaging

Assembly:

mscorlib.dll

Retrieves an object with the specified name from the CallContext.

public:
 static System::Object ^ GetData(System::String ^ name);

[System.Security.SecurityCritical]
public static object GetData (string name);

[<System.Security.SecurityCritical>]
static member GetData : string -> obj

Public Shared Function GetData (name As String) As Object

Parameters

name

String

The name of the item in the call context.

Returns

Object

The object in the call context associated with the specified name.

Attributes

SecurityCriticalAttribute

Exceptions

SecurityException

The immediate caller does not have infrastructure permission.

Examples

The following code example demonstrates the use of the GetData method to transmit Principal and Identity Objects to a remote location for identification. To view the code for the LogicalCallContextData class used in this sample, see the example for the ILogicalThreadAffinative interface. To view the code for the client class used in the sample, see the example for the CallContext class. To view the code for the server class used in this sample, see the example for the RegisterActivatedServiceType class.

using namespace System;
using namespace System::Text;
using namespace System::Runtime::Remoting::Messaging;
using namespace System::Security::Principal;
using namespace System::Security::Permissions;

ref class LogicalCallContextData;

public ref class HelloServiceClass: public MarshalByRefObject
{
private:
   static int n_instances;
   int instanceNum;

public:
   HelloServiceClass()
   {
      n_instances++;
      instanceNum = n_instances;
      Console::WriteLine(  "{0} has been created.  Instance # = {1}", this->GetType()->Name, instanceNum );
   }

   ~HelloServiceClass()
   {
      Console::WriteLine( "Destroyed instance {0} of HelloServiceClass.", instanceNum );
   }

   [SecurityPermissionAttribute(SecurityAction::Demand, Flags=SecurityPermissionFlag::Infrastructure)]
   String^ HelloMethod( String^ name )
   {
      //Extract the call context data
      LogicalCallContextData^ data = dynamic_cast<LogicalCallContextData^>(CallContext::GetData( "test data" ));
      IPrincipal^ myPrincipal = data->Principal;

      //Check the user identity
      if ( myPrincipal->Identity->Name == "Bob" )
      {
         Console::WriteLine( "\nHello {0}, you are identified!", myPrincipal->Identity->Name );
         Console::WriteLine( data->numOfAccesses );
      }
      else
      {
         Console::WriteLine( "Go away! You are not identified!" );
         return String::Empty;
      }

      // calculate and return result to client    
      return String::Format( "Hi there {0}.", name );
   }
};

using System;
using System.Text;
using System.Runtime.Remoting.Messaging;
using System.Security.Principal;
using System.Security.Permissions;

public class HelloServiceClass : MarshalByRefObject {

   static int n_instances;
   int instanceNum;

   public HelloServiceClass() {
      n_instances++;
      instanceNum = n_instances;
      Console.WriteLine(this.GetType().Name + " has been created.  Instance # = {0}", instanceNum);
   }

   ~HelloServiceClass() {
      Console.WriteLine("Destroyed instance {0} of HelloServiceClass.", instanceNum);
   }

   public String HelloMethod(String name) {

      //Extract the call context data
      LogicalCallContextData data = (LogicalCallContextData)CallContext.GetData("test data");
      IPrincipal myPrincipal = data.Principal;

      //Check the user identity
      if(myPrincipal.Identity.Name == "Bob") {
         Console.WriteLine("\nHello {0}, you are identified!", myPrincipal.Identity.Name);
         Console.WriteLine(data.numOfAccesses);
      }
      else {
         Console.WriteLine("Go away! You are not identified!");
         return String.Empty;
      }

        // calculate and return result to client	
      return "Hi there " + name + ".";
   }
}

Imports System.Text
Imports System.Runtime.Remoting.Messaging
Imports System.Security.Principal
Imports System.Security.Permissions

Public Class HelloServiceClass
   Inherits MarshalByRefObject
   
   Private Shared n_instances As Integer
   Private instanceNum As Integer  
   
   Public Sub New()
      n_instances += 1
      instanceNum = n_instances
      Console.WriteLine(Me.GetType().Name + " has been created.  Instance # = {0}", instanceNum)
   End Sub

   
   Protected Overrides Sub Finalize()
      Console.WriteLine("Destroyed instance {0} of HelloServiceClass.", instanceNum)
      MyBase.Finalize()
   End Sub
  
   <PermissionSet(SecurityAction.LinkDemand)> _
   Public Function HelloMethod(name As [String]) As [String]
      
      'Extract the call context data
      Dim data As LogicalCallContextData = CType(CallContext.GetData("test data"), LogicalCallContextData)
      Dim myPrincipal As IPrincipal = data.Principal
      
      'Check the user identity
      If myPrincipal.Identity.Name = "Bob" Then
         Console.WriteLine()
         Console.WriteLine("Hello {0}, you are identified!", myPrincipal.Identity.Name)
         Console.WriteLine(data.numOfAccesses)
      Else
         Console.WriteLine("Go away! You are not identified!")
         Return [String].Empty
      End If
      
      ' calculate and return result to client	
      Return "Hi there " + name + "."
   End Function 'HelloMethod

End Class