Inheritance

class Animal {
    protected string Name;

    public Animal(string name) {
        Name = name;
    }

    public virtual void MakeSound() {
        Console.WriteLine($"{Name} makes a sound");
    }
}

class Dog : Animal {
    public Dog(string name) : base(name) {}

    public override void MakeSound() {
        Console.WriteLine($"{Name} barks");
    }
}

Dog rex = new Dog("Rex");
rex.MakeSound(); // Rex barks

A base method must be marked virtual (or abstract) to allow overriding — like C++, and unlike Java, C# does not make every method overridable by default. : base(name) calls the parent's constructor, equivalent to Java's super(name).

Common mistakes

• Forgetting virtual on the base method — without it, override on the subclass is a compile error, catching the mistake immediately rather than silently doing the wrong thing.

Practice

Create a Cat class extending Animal that overrides MakeSound() to print "<Name> meows".

class Cat : Animal {
    public Cat(string name) : base(name) {}

    public override void MakeSound() {
        Console.WriteLine($"{Name} meows");
    }
}