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Is there any way to call the parent version of an overridden method? (C# .NET)

In the code below I tried in two ways to access the parent version of methodTwo, but the result was always 2. Is there any way to get the 1 result from a ChildClass instance without modifying these two classes?

class ParentClass
{
    public int methodOne()
    {
        return methodTwo();
    }

    virtual public int methodTwo()
    {
        return 1;
    }
}

class ChildClass : ParentClass
{
    override public int methodTwo()
    {
        return 2;
    }
}

class Program
{
    static void Main(string[] args)
    {
        var a = new ChildClass();
        Console.WriteLine("a.methodOne(): " + a.methodOne());
        Console.WriteLine("a.methodTwo(): " + a.methodTwo());
        Console.WriteLine("((ParentClass)a).methodTwo(): "
         + ((ParentClass)a).methodTwo());
        Console.ReadLine();
    }
}

Update ChrisW posted this:

From outside the class, I don't know any easy way; but, perhaps, I don't know what happens if you try reflection: use the Type.GetMethod method to find the MethodInfo associated with the method in the ParentClass, and then call MethodInfo.Invoke

That answer was deleted. I'm wondering if that hack could work, just for curiosity.

See Question&Answers more detail:os

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by (71.8m points)

Inside of ChildClass.methodTwo(), you can call base.methodTwo().

Outside of the class, calling ((ParentClass)a).methodTwo() will call ChildClass.methodTwo. That's the whole reason why virtual methods exist.


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