title: I have implemented AfterReceiveRequest method (from IDispatchMessageInspector) and within that want to verify if request is valid?
body: <p>In my Client before calling the service i added a token (guid) to the request before sending to wcf service. </p>
  
  <pre><code>AfterReceiveRequest(ref System.ServiceModel.Channels.Message request, System.ServiceModel.IClientChannel channel, System.ServiceModel.InstanceContext instanceContext)
  </code></pre>
  
  <p>Within this method, I want to verify if the request header has the token(guid) that was added in the client. So i used this part of code here:</p>
  
  <pre><code>Guid securityTokenId = request.Headers.GetHeader&lt;Guid&gt;("Token", "System");
  </code></pre>
  
  <p>If in any case this "Token" is not found in the header will my <code>securityTokenId</code> return <code>Guid.Empty</code>? or what does it return?</p>