Question

I’ve got an abstract class like this;

public abstract PropertyBase
{
    public static System.Type GetMyType()
    {
      return !!!SOME MAGIC HERE!!!
    }
}

I’d like to subclass it, and when I call the static GetMyType(), I’d like to return the subclass’s type. So if I declare a subtype;

public class ConcreteProperty: PropertyBase {}

then when I call

var typeName = ConcreteProperty.GetMyType().Name;

I expect ‘typeName’ to be set to “ConcreteProperty.” I suspect there’s no way to do it, but I’m interested if anyone out there knows a way to get this info.

(The particular problem I’m trying to solve is the verbosity of dependency properties in WPF; I’d love to be able to do something like this;

class NamedObject : DependencyObject
{
    // declare a name property as a type, not an instance.
    private class NameProperty : PropertyBase<string, NamedObject> { }

    // call static methods on the class to read the property
    public string Name
    {
        get { return NameProperty.Get(this); }
        set { NameProperty.Set(this, value); }
    }
}

And I almost have an implementation, but I can’t quite get the info I need out of my NameProperty class.)

Answer 1

You can partially achieve (1-level of inheritance deep) using generics:

class PropertyBase<T>
{
    public static Type GetMyType() { return typeof (T); }
}

// the base class is actually a generic specialized by the derived class type
class ConcreteProperty : PropertyBase<ConcreteProperty> { /* more code here */ }

// t == typeof(ConcreteProperty)
var t = ConcreteProperty.GetMyType();