Change type of ViewData in extended controller

Question

I created my own CustomController base class that inherits from Controller. Likewise I created my own CustomViewData that inherits from ViewDataDictionary. The CustomController class has a ctor that accepts a CustomViewData as parameter.

All my controllers inherit from CustomController and pass in their inherited CustomViewData. Now I want to be able to call this.ViewData from within my controller and get back the view data I passed in at the controller. Currently I get back a ViewDataDictionary (from the Controller class). So I lost my type information.

How can I retain my type information on my ViewData property in my CustomController derived class without wrapping it in a get/set that does the boxing for me?

Answer 1

ViewData property is defined in ControllerBase class and you can't override it, but you can do this:

public class CustomController : Controller {

    public new CustomViewData ViewData { get; set; }

}

But be warned, if you access a CustomController instance like this

Controller c = myCustomControllerInstance;
CustomViewData cvd = c.ViewData;

your code won't compile since you'll be using the default implementation of ViewData property and it will return a ViewDataDictionary instance.

Answer 2

I tried several ways to accomplish my goal, but none seem to work save for this ugly solution I knew existed but is .. well, ugly.
I basically wrap the boxing/unboxing in a get/set. I have to do this throughout the entire class chain. So my CommonController does this with a CommonViewData instance, my AbcController:CommonController does this from AbcViewData:CommonViewData to CommonViewData etc. Untill I find a better solution, I'll have to go with this.

public new AbcViewData ViewData { 
    get { return base.ViewData as [bcViewData; }
    set { base.ViewData = value; }
}