Question

I am trying to do something like this in C#

public class ParentClass {
  public static ParentClass GetSomething()
  {
    var thing = new // ?????
    return thing;
  }
}

public class ChildClass : ParentClass {
}

And then I want to be able to call the static method on the child class like so:

ChildClass blah = ChildClass.GetSomething();

e.g. When calling the static method on the child class I want to instantiate an instance of the child class. But I just want the static method defined on the parent. Is this at all possible? I’d be happy even with:

ChildClass blah = (ChildClass) ChildClass.GetSomething();

Thanks!

Answer 1

You cannot ‘override’ static methods. But you can use generics to tell the ParentClass which derived class you actually means. It’s somewhat ugly but it works:

class ParentClass<T> where T : ParentClass<T>, new()
{
    public static T GetSomething()
    {
        T thing = new T();
        return thing;
    }
}

class ChildClass : ParentClass<ChildClass>
{
}

Test:

ChildClass x = ChildClass.GetSomething(); // works