title: ASP.NET MVC - access parameters NOT posted via form
body: <p><br/>
  <br/>
  <strong>Current Scenario</strong>  <br/><br/>
  I am using MVC 4, .net 4.5 on vs2012. I have an action which accepts a custom type. This custom type(model) is tightly bound to a view. I am making a POST via AJAX using JSON. Post will only post the relevant data and no form. Its content type is "application/json; charset=UTF-8". I am getting a nicely populated(read valid) model in my action.
  <br/>
  <br/>
  <strong>The issue</strong>  <br/>
  Now I need to add a custom filter but I am unable to access the data via Request, Request.Form, Request.Param? I have been looking in System.Web.HttpContext.Current. If data is getting populated in my model, then it has to be somewhere in the request itself. I guess I am missing the finer print.
    <br/><br/>
  The javascript for posting data is somewhat like  <br/><br/></p>
  
  <pre><code>$("#postData").click(function (event) {
  
      var savedObject = getJson(savedObject, parentContext);
  
      $.ajax({
          url: '/controller/action',
          contentType: 'application/json',
          dataType: 'json',
          data: savedObject,
          type: "POST",
          success: successCallBack,
          error: errorCallBack
      });
  });
  </code></pre>