title: jQuery Ajax post is sending null to my MVC controller
body: <p>I'm not sure why this is happening. I have a string array that should be sent to a controller action that's expecting a string array. This is my jQuery:</p>
  
  <pre><code>$.post("/@Model.Controller/@Model.Action", { "choices": ajax }, function (result) {
                  $("#label" + "@Model.Id").html(result);
              });
  </code></pre>
  
  <p>This is my controller action:</p>
  
  <pre><code>public JsonResult UpdateMultipleType(string[] choices)
      {
          return Json(choices);
      }
  </code></pre>
  
  <p>I took a look in Firebug and in the Post Tab, the headers read:</p>
  
  <pre><code>Parametersapplication/x-www-form-urlencoded
  choices[]   Comedy
  choices[]   Thriller
  choices[]   Action
  choices[]   Adventure
  </code></pre>
  
  <p>I've debugged and confirmed that it is hitting UpdateMultipleType and that the string array "choices" is null when that action is called. The call goes through but since we're returning null, I get a Javascript error after the call completes.</p>
  
  <p>I don't know why my controller action is being sent null when it's clear that there is an array called choices being sent over.</p>