Question

I always thought base.Something was equivalent to ((Parent)this).Something, but apparently that’s not the case. I thought that overriding methods eliminated the possibility of the original virtual method being called.

Why is the third output different?

void Main() {
    Child child = new Child();

    child.Method();             //output "Child here!"
    ((Parent)child).Method();   //output "Child here!"
    child.BaseMethod();         //output "Parent here!"
}

class Parent {
    public virtual void Method() { 
        Console.WriteLine("Parent here!"); 
    }
}

class Child : Parent {
    public override void Method() { 
        Console.WriteLine ("Child here!"); 
    }
    public void BaseMethod() { 
        base.Method(); 
    }
}

Answer 1

Because in BaseMethod you explicitly call the method in the base class, by using the base keyword. There is a difference between calling Method() and base.Method() within the class.

In the documentation for the base keyword, it says (amongst other things) that it can be used to Call a method on the base class that has been overridden by another method.