In MVC3 how do I get a DataContract-attributed object that was posted to my action?

Question

I have to implement a method that i declared like this:

[OperationContract]
[WebInvoke(Method = "POST", UriTemplate = @"whatever")]
void MyMethod(InputContainer input);

where InputContainer is declared as a DataContract:

[DataContract(Namespace = "whatever")]
public class InputContainer : IExtensibleDataObject
{
    //[DataMember]s inside
}

Now in my code I have an action to which the call will be mapped:

[HttpPost]
ActionResult MyMethod()
{
    // How do I get the InputContainer object here?
}

I've only seen samples using ReadAsAsync() which is a dependency on one more assembly which I'd like t avoid. Anyway I suspect ReadAsAsync() is some helper method that I could replicate.

How do I get the DataContract-attributed object POSTed to my MVC3 action?

Answer 1

This won't work out of the box. If I add a parameter of type InputContainer to my action - it will be default-initialized, the values in the POST body will be ignored.

Extra wiring from here is needed. First an implementation of IModelBinder is needed that will access the HTTP request InputStream and deserialize the object with DataContractSerializer. Then a subclass of CustomModelBinderAttribute is needed that would return the abovementioned IModelBinder implementations form its GetBinder() implementation. Let's pretend it is called MagicAttribute. Once all this is done all is needed is adding the attribute to the parameter:

[HttpPost]
ActionResult MyMethod([Magic] InputContainer input)
{
}