IClientMessageInspector.BeforeSendRequest(Message, IClientChannel) Method

public:
 System::Object ^ BeforeSendRequest(System::ServiceModel::Channels::Message ^ % request, System::ServiceModel::IClientChannel ^ channel);

public object BeforeSendRequest(ref System.ServiceModel.Channels.Message request, System.ServiceModel.IClientChannel channel);

abstract member BeforeSendRequest : Message * System.ServiceModel.IClientChannel -> obj

Public Function BeforeSendRequest (ByRef request As Message, channel As IClientChannel) As Object

The object that is returned as the correlationState argument of the AfterReceiveReply(Message, Object) method. This is null if no correlation state is used.

The best practice is to make this a Guid to ensure that no two correlationState objects are the same.

The following code example shows an implementation that writes strings to the console when the implementation is called.

#region IClientMessageInspector Members
public void AfterReceiveReply(ref System.ServiceModel.Channels.Message reply, object correlationState)
{
  Console.WriteLine("IClientMessageInspector.AfterReceiveReply called.");
  Console.WriteLine("Message: {0}", reply.ToString());
}

public object BeforeSendRequest(ref System.ServiceModel.Channels.Message request, IClientChannel channel)
{
  Console.WriteLine("IClientMessageInspector.BeforeSendRequest called.");
  return null;
}

#Region "IClientMessageInspector Members"
    Public Sub AfterReceiveReply(ByRef reply As System.ServiceModel.Channels.Message, _
                       ByVal correlationState As Object) Implements IClientMessageInspector.AfterReceiveReply
        Console.WriteLine("IClientMessageInspector.AfterReceiveReply called.")
        Console.WriteLine("Message: {0}", reply.ToString())
    End Sub

    Public Function BeforeSendRequest(ByRef request As System.ServiceModel.Channels.Message, _
            ByVal channel As IClientChannel) As Object Implements IClientMessageInspector.BeforeSendRequest
        Console.WriteLine("IClientMessageInspector.BeforeSendRequest called.")
        Return Nothing
    End Function

The following code example shows how to use an System.ServiceModel.Description.IEndpointBehavior to insert the client message inspector in the client endpoint.

#region IEndpointBehavior Members
public void AddBindingParameters(
  ServiceEndpoint endpoint, BindingParameterCollection bindingParameters
) { return; }

public void ApplyClientBehavior(ServiceEndpoint endpoint, ClientRuntime clientRuntime)
{
  clientRuntime.MessageInspectors.Add(new Inspector());
  foreach (ClientOperation op in clientRuntime.Operations)
    op.ParameterInspectors.Add(new Inspector());
}

public void ApplyDispatchBehavior(ServiceEndpoint endpoint, EndpointDispatcher endpointDispatcher)
{
  endpointDispatcher.DispatchRuntime.MessageInspectors.Add(new Inspector());
  foreach (DispatchOperation op in endpointDispatcher.DispatchRuntime.Operations)
    op.ParameterInspectors.Add(new Inspector());
}

public void Validate(ServiceEndpoint endpoint){ return; }

#Region "IEndpointBehavior Members"
    Public Sub AddBindingParameters(ByVal endpoint As ServiceEndpoint, ByVal bindingParameters _
                                    As BindingParameterCollection) Implements IEndpointBehavior.AddBindingParameters
        Return
    End Sub

    Public Sub ApplyClientBehavior(ByVal endpoint As ServiceEndpoint, ByVal clientRuntime As ClientRuntime) _
    Implements IEndpointBehavior.ApplyClientBehavior
        clientRuntime.MessageInspectors.Add(New Inspector())
        For Each op As ClientOperation In clientRuntime.Operations
            op.ParameterInspectors.Add(New Inspector())
        Next op
    End Sub

    Public Sub ApplyDispatchBehavior(ByVal endpoint As ServiceEndpoint, ByVal endpointDispatcher As  _
                                     EndpointDispatcher) Implements IEndpointBehavior.ApplyDispatchBehavior
        endpointDispatcher.DispatchRuntime.MessageInspectors.Add(New Inspector())
        For Each op As DispatchOperation In endpointDispatcher.DispatchRuntime.Operations
            op.ParameterInspectors.Add(New Inspector())
        Next op
    End Sub

Public Sub Validate(ByVal endpoint As ServiceEndpoint) Implements IEndpointBehavior.Validate
    Return
End Sub

Finally, the following code example shows how to modify the client configuration file to use the endpoint behavior with a particular endpoint.

  <client>
      <endpoint 
        address="http://localhost:8080/SampleService" 
        behaviorConfiguration="clientInspectorsAdded" 
        binding="wsHttpBinding"
        bindingConfiguration="WSHttpBinding_ISampleService" 
        contract="ISampleService"
        name="WSHttpBinding_ISampleService"
      >
      </endpoint>
  </client>
<behaviors>
  <endpointBehaviors>
    <behavior name="clientInspectorsAdded">
      <clientInterceptors />
    </behavior>
  </endpointBehaviors>
</behaviors>
<extensions>
  <behaviorExtensions>
    <add 
      name="clientInterceptors" 
      type="Microsoft.WCF.Documentation.InspectorInserter, HostApplication, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null"
  />
  </behaviorExtensions>
</extensions>

Implement the BeforeSendRequest to inspect or modify a request message before it is sent.