Inheritance in C#

One base contract, many behaviors, chosen at run time.

Animal[] zoo = { new Dog(), new Cat() };
foreach (var animal in zoo)
{
    Console.WriteLine(animal.Speak());
}

class Animal
{
    public virtual string Speak() => "...";
}

class Dog : Animal
{
    public override string Speak() => "woof, says the dog";
}

class Cat : Animal
{
    public override string Speak() => "meow, says the cat";
}

How it works

virtual marks what a subclass may change; override changes it.
An Animal[] holds dogs and cats; each speaks as itself.
The base implementation is the default when nobody overrides.

Keywords and builtins used here

Animal
Cat
Dog
Speak
class
foreach
in
new
override
public
string
var
virtual

The run, in numbers

Lines: 20
Characters to type: 325
Tokens: 80
Three-star pace: 90 tpm

At the three-star pace of 90 tokens a minute, this run takes about 53 seconds.

Type this snippet

Step 3 of 4 in Classes & records, step 20 of 29 in Language basics.

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Inheritance in other languages