<SecurityPermission(SecurityAction.LinkDemand, Flags := SecurityPermissionFlag.Infrastructure)> _
Public Sub ProcessMessageStart(requestMessage As IMessage, bClientSide As Boolean, bAsyncCall As Boolean) Implements IDynamicMessageSink.ProcessMessageStart

   Console.WriteLine(ControlChars.Cr + "ProcessMessageStart")
   Console.WriteLine("requestMessage = {0}", requestMessage)
   
   Try
      Console.WriteLine("SessionId = {0}.", RemotingServices.GetSessionIdForMethodMessage(CType(requestMessage, IMethodMessage)))
   Catch e As InvalidCastException
      Console.WriteLine("The requestMessage is not an IMethodMessage.")
   End Try
   
   Dim requestMethodCallMessage As IMethodCallMessage
   
   Try
      requestMethodCallMessage = CType(requestMessage, MethodCall)
      
      ' Prints the details of the IMethodCallMessage to the console
      Console.WriteLine(ControlChars.Cr + "MethodCall details")
      Console.WriteLine("Uri = {0}", requestMethodCallMessage.Uri)
      Console.WriteLine("TypeName = {0}", requestMethodCallMessage.TypeName)
      Console.WriteLine("MethodName = {0}", requestMethodCallMessage.MethodName)
      Console.WriteLine("ArgCount = {0}", requestMethodCallMessage.ArgCount)
      Console.WriteLine("MethodCall.Args")
      
      Dim o As Object
      For Each o In  requestMethodCallMessage.Args
         Console.WriteLine(ControlChars.Tab + "{0}", o)
      Next o 
      
      ' Sends this method call message to another server to replicate
      ' the call at the second server
      If requestMethodCallMessage.Uri = replicatedServiceUri Then
         
         Dim replicationService As SampleService = CType(Activator.GetObject(GetType(SampleService), replicationServerUrl + replicatedServiceUri), SampleService)
         Dim returnMessage As IMethodReturnMessage = RemotingServices.ExecuteMessage(replicationService, requestMethodCallMessage)
         
         ' Prints the results of the method call stored in the IMethodReturnMessage.
         Console.WriteLine(ControlChars.Cr + "Message returned by ExecuteMessage.")
         Console.WriteLine(ControlChars.Tab + "Exception = {0}", returnMessage.Exception)
         Console.WriteLine(ControlChars.Tab + "ReturnValue = {0}", returnMessage.ReturnValue)
         Console.WriteLine(ControlChars.Tab + "OutArgCount = {0}", returnMessage.OutArgCount)
         Console.WriteLine("Return message OutArgs")
         For Each o In  requestMethodCallMessage.Args
            Console.WriteLine(ControlChars.Tab + "{0}", o)
         Next o
         
      End If
      
   Catch e As InvalidCastException
      Console.WriteLine("The requestMessage is not a MethodCall")
   End Try

End Sub