title: WebApi: mapping parameter to header value
body: <p>I've done a few searches but haven't seem to find anything... </p>
  
  <p>Using WebApi, I would like to map an input parameter to a header value:  e.g.</p>
  
  <p>E.g. in controller:</p>
  
  <pre><code>public User GetUser(int id){
     ...
     return user;
  }
  </code></pre>
  
  <p>I want WebApi to map the id parameter to a header value (e.g. X-Auth: 1234)... rather than an URL parameter.</p>
  
  <p>Is this supported?</p>