title: Request.Files is empty when using input type file with ASP.Net MVC
body: <p>When posting back to my controller my model is populated with correct values and my string field has the file name, but Request.Files is empty.</p>
  
  <p>My input at the view is:</p>
  
  <pre><code>&lt;input id="SitePlan" name="SitePlan" type="file" value="&lt;%= Html.Encode(Model.SitePlan) %&gt;" /&gt;
  </code></pre>
  
  <p>My form tag begins with:</p>
  
  <pre><code> &lt;% using (Html.BeginForm(new { enctype = "multipart/form-data" }))
  </code></pre>
  
  <p>Is there anything else I need to set to send the field back to the controller?</p>