IClientMessageInspector.BeforeSendRequest(Message, IClientChannel) 方法

定义

在将请求消息发送到服务之前,启用消息的检查或修改。

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

参数

request
Message

要发送给服务的消息。

channel
IClientChannel

WCF 客户端对象通道。

返回

Object

作为 AfterReceiveReply(Message, Object) 方法的 correlationState 参数返回的对象。 如果不使用关联状态,则为 null

最佳做法是将它设置为 Guid,以确保没有两个相同的 correlationState 对象。

示例

下面的代码示例显示一个实现,当调用该实现时将字符串写入控制台。

#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

下面的代码示例显示如何使用 System.ServiceModel.Description.IEndpointBehavior 在客户端终结点中插入客户端消息检查器。

#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

最后,下面的代码示例显示如何修改客户端配置文件,将终结点行为与特定的终结点一起使用。

  <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>

注解

在发送请求消息之前,实现 BeforeSendRequest 来检查或修改请求消息。

适用于