oop检查返回类型是父类还是子类

Question

Suppose I have this class:

public class Parent
{
    public string Name {get; set;}
}

and this class, which inherits from Parent:

public class Child : Parent
{
    public string Toys {get; set;}
}

In some random class, I have a function that returns Parent:

public class SomeClass
{
    public Parent GetPerson()
    {
      if (whatever)
      {
        return new Parent { Name = 'Parent' };
      }
      else
      {
        return new Child {Name = 'Child', Toys = 'Paper Plane, Spider Man'};
      }
    }
}

when I call this GetPerson, I want to know if it is a Parent or a Child. I thought this might work, but this condition is always false

var person = GetPerson();

if (person is Child childPerson) // This is always false :(
{
   var toys = childPerson.Toys;
}

Answer 1

I copied and pasted the "if" statement and it does return true when person is in fact "Child" type. Make sure that person's type is indeed of type child at the time you enter the if condition. This would presume that GetPerson(); always returns a parent.

Answer 2

Did you try GetType() and typeof() ?

Example:

if (person.GetType() == typeof(Child))
{
   ...
}

Regards