title: Does RestSharp overwrite manually set Content-Type?
body: <p>I'm creating a RestSharp.RestRequest via:</p>
  
  <pre><code>RestRequest request = new RestRequest();
  request.Method = Method.POST;
  request.Resource = "/rest-uri";
  
  request.AddHeader("Content-Type", "application/someContentType");
  
  string xml = "&lt;?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?&gt;" + Environment.NewLine +
               "&lt;register-request"&gt;" + Environment.NewLine +
               "    &lt;name=\"someName\"/&gt;" + Environment.NewLine +
               "&lt;/register-request&gt;");
  
  request.AddParameter("text/xml", registerSinkRequest, ParameterType.RequestBody);
  </code></pre>
  
  <p>(The Content-Type is manually set to <code>application/someContentType</code>)</p>
  
  <p>In debug-mode it also shows <code>Content-Type=application/someContentType</code></p>
  
  <p>But executing the RestRequest returns an <code>415 Media Not Supported</code>-Error and WireShark shows that the Media-Type is set to <code>text/xml</code> (like set in the AddParameter-Method).</p>
  
  <p>Why is RestSharp showing a different Content-Type then WireShark? And how can I prevent the Content-Type to be changed (if it is)?</p>