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c#genericsinheritancetype-parameter

C# - Specifying type parameters of super-class in sub-classes?

I am trying to do the following in C#.

public class Parent<T> where T : Parent<???>
{
  public T Prop { get; set; }
}

public class Child : Parent<Child>
{
}

How can I do it?

Solution

  • This works fine:

    public class Parent<T> where T : Parent<T>
{
  public T Prop { get; set; }
}

public class Child : Parent<Child>
{
}

    Do be careful with this as c# does not enforce a true Parent/Child relationship. For example, given the above code, it is also legal for me to then do this:

    public class Stranger : Parent<Child>
{
}

    If you write unit tests then it's worth writing a type checker that looks for this mispattern.