ASP.MVC2 receive JSON request using JsonValueProviderFactory but without a Type
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I am using the JsonValueProviderFactory in an MVC2 web app to handle JSON requests inbound from an iOS iPad app.

I don't want to map my JSON to a type.  I just want to receive the raw JSON and pass it on to a model for processing.  What signature should my controller action have to allow me to access the raw JSON being passed to my controller?

Here are the three I've tried so far; none of them work:

    [ValidateInput(false)] // Allow dodgy chars in the JSON e.g. "<aa>"
            [HttpPost]
            //public ActionResult PushObject(FormCollection form) // no joy
            //public ActionResult PushObject(List<string> parms) // no joy
            //public ActionResult PushObject(string jsonRequest) // no joy
            {...