Manually build View Model from Request Data - ajax

Question

I have a page that currently submits via Ajax to a controller method. MVC automatically converts the request data into my View Model type, and that's great.
Now I'm trying to change it so instead of an Ajax post, it makes a SignalR call instead. I want to submit the same data via SignalR (via $('form').serialize()), and then parse the data into my view model type.
Example:
//controller
public ActionResult MyMethod(MyViewModel vm){
//vm is automatically created from form data
}
//SignalR Hub
public void MyMethodViaSignalR(string formData){
//how can I turn formData or Context.Request into a MyViewModel?
}
//Make the SignalR call
myHub($('form').serialize());

Answer 1

I found a generic solution. I put this code in my Base Controller (you could copy it to any one controller as well), and it will build whatever view model you need.
protected class SignalRRequestJSon
{
public string H { get; set; }
public string M { get; set; }
public List<string> A { get; set; }
public int I { get; set; }
}
public T GetModel<T>(HttpRequest req) where T : class, new()
{
var obj = JsonConvert.DeserializeObject<SignalRRequestJSon>(req["data"]);
var stringWriter = new System.IO.StringWriter();
var httpResponse = new HttpResponse(stringWriter);
var url = req.UrlReferrer.ToString(); // this value doesn't matter, but needs to be a valid url.
var queryStringData = obj.A[0];
var httpRequest = new HttpRequest("", url, queryStringData);
var httpContext = new HttpContext(httpRequest, httpResponse);
var routeData = new RouteData();
routeData.Values.Add("controller", this.GetType().Name.ToLower().Replace("controller", ""));
routeData.Values.Add("action", "Arbitrary");
this.ControllerContext = new ControllerContext(new HttpContextWrapper(httpContext), routeData, this);
var valueProvider = new QueryStringValueProvider(this.ControllerContext);
this.ValueProvider = valueProvider;
var vm = new T();
UpdateModel(vm, valueProvider);
return vm;
}
public ActionResult Arbitrary<T>(T model)
{
return View();
}
Called like this from my SignalR hub:
var controller = DependencyResolver.Current.GetService<MyController>();
var vm = controller.GetModel<MyViewModel>(HttpContext.Current.Request);