title: ASP.NET MVC POST Parameter into RouteData
body: <p>I'm using jQuery to POST an Id to my route, for example:<br>
  <a href="http://localhost:1234/Load/Delete" rel="nofollow noreferrer">http://localhost:1234/Load/Delete</a><br>
  with a POST Parameter Id = 1</p>
  
  <p>I'm only using the default route in Global.asax.cs right now:</p>
  
  <pre><code>routes.MapRoute(
      "Default",
      "{controller}/{action}/{id}",
      new { controller = "Home", action = "Index", id = "" }
  );
  </code></pre>
  
  <p>When I perform the POST, in my ActionFilter <code>filterContext.RouteData.Values["Id"]</code> is set to the default value of <code>""</code>. Ideally, I'd like it to use the POST Parameter value automatically if the URL comes up with <code>""</code>. I know it is posting properly because I can see the value of <code>"1"</code> in <code>filterContext.HttpContext.Request.Params["Id"]</code>.</p>
  
  <p>Is there a way to get RouteData to use a POST parameter as a fall back value?</p>