I have a MVC 4 project where I would like to use functionality similar to `DisplayFromat`, but setting a `DataFormatString` is not enough. I would like a function to be called to format the string. Is that possible?

I have tested inheriting `DisplayFormat` but that just lets me set the `DataFormatString`.

I have looked at customizing `DataAnnotationsModelMetadataProvider`, but I don't see how I would make it call a custom function for formatting.

My particular case is that I need to format the integer 201351 as "w51 2013". I couldn't come up with a format string that does that.