I'm creating a new project, asp.net mvc3 with Razor, and wanting to turn the LogOn into an ajax request.

HTML

@using (Ajax.BeginForm("LogOn", "Account", new AjaxOptions { HttpMethod="post", OnSuccess="LoginSubmitted"}))
{
}

Controller

if (Request.IsAjaxRequest())
{
    return Json(new { ResultMessage = "Username or password provided is incorrect"});
}
else
{
    ModelState.AddModelError("", "The user name or password provided is incorrect.");
}

Everything else remains the same.

First, looking at the the http response with Fiddler, I notice there is no x-requested-with header. So I add

<input type="hidden" name="X-Requested-With" value="XMLHttpRequest" />

That seems to work, but now what I receive back is a Json object, which isn't being parsed and instead Google Chrome is just rendering the Json to screen.

Whats happening?