Method overriding or method hiding?

Valerie Meunier

I read something about Method overriding or method hiding. I know how it works, but what's the best cjoice between hiding or overriding? Are they made for particular situation?

Thanks

3 Replies

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Rajanikant Hawaldar5y ago
Accepted answer
In method hiding: you just simply create a method in a parent class and in child class you need to define that method using new keyword. In method hiding, you can completely redefine the method. Here hiding is a reference type. If you do not use the new keyword, then the compiler will automatically hide the method of the base class. In the method hiding, when base class reference variable pointing to the object of the derived class, then it will call the hidden method in the base class.
Example:
using System;

// Base Class
public class My_Parent {

    public void show()
    {
        Console.WriteLine("This is my parent class.");
    }
}

// Derived Class
public class My_Child : My_Parent {

    // Hide the method of base class
    // Using new keyword
    public new void show() {

        Console.WriteLine("This is my child class.");
    }
}

public class GFG {

    // Main method
    static public void Main()
    {

        // Creating the object of
        // the derived class
        My_Child obj = new My_Child();

        // Access the method of derived class
        obj.show();
    }
}
output : This is my child class.
In Method Overriding : In method overriding, you need to define the method of a parent class as a virtual method using virtual keyword and the method of child class as an overridden method using override keyword. It only redefines the implementation of the method. Here overriding is an object type. If you do not use override keyword, then the compiler will not override the method. Instead of the overriding compiler will hide the method. In method overriding, when base class reference variable pointing to the object of the derived class, then it will call the overridden method in the derived class.
Example:
// Method overriding concept
using System;

// Base class
class My_Parent {

    // virtual method
    public virtual void display()
    {
        Console.WriteLine("My new parent class.. !");
    }
}

// Derived class
class My_Child : My_Parent {

    // Here display method is overridden
    public override void display()
    {
        Console.WriteLine("My new child class.. !");
    }
}

class GFG {

    // Main Method
    public static void Main()
    {

        My_Parent obj;

        // Creating object of the base class
        obj = new My_Parent();

        // Invoking method of the base class
        obj.display();

        // Creating object of the derived class
        obj = new My_Child();

        // Invoking method of derived class
        obj.display();
    }
}
Output:
My new parent class.. !
My new child class.. !
Sachin Singh5y ago
You must be already knowing what they do, both do the same thing that is reimplementing a parent class method in the child class. Then the question that arises is what is the difference then?

Override means reimplement the method in the child class with the permission of the parent.
Hiding means reimplement the method in the child class without the permission of the parent.

as in the first case, the parent knows that his method is now overridden by the child class, so you call the child class method with the parent class reference then also the child method executes.
Parent p= new Child();
p.Method(); // child class method will execute

// because parent know that yes I only had given the permission to the child //class, so he reimplemented the method.
but in the case of method hiding, the parent doesn't know that a child has re-implemented his method. so if you call the child method with the parent reference then the parent method executes and not the child method.
Parent p= new Child();
p.Method(); // parent class method will execute
//because the parent had never given him the permission to override the method, the child forcefully overidden the parent's method.
Valerie Meunier5y ago
Thanks