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// A new delegate pointing to targets returning SportsCar types.

public delegate SportsCar ObtainSportsCarDelegate();

As we now have two delegate types, we now must create an instance of each to obtain Car and

SportsCar types:

class Program

{

public delegate Car ObtainCarDelegate();

public delegate SportsCar ObtainSportsCarDelegate();

public static Car GetBasicCar()

{ return new Car(); }

public static SportsCar GetSportsCar()

{ return new SportsCar(); }

static void Main(string[] args)

{

ObtainCarDelegate targetA = new ObtainCarDelegate(GetBasicCar);

Car c = targetA();

Console.WriteLine("Obtained a {0}", c);

ObtainSportsCarDelegate targetB =

new ObtainSportsCarDelegate(GetSportsCar);

SportsCar sc = targetB();

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Console.WriteLine("Obtained a {0}", sc);

Console.ReadLine();

}

}

Given the laws of classic inheritance, it would be ideal to build a single delegate type that can

point to methods returning either Car or SportsCar objects (after all, a SportsCar “is-a” Car).

Covariance (which also goes by the term relaxed delegates) allows for this very possibility. Simply

put, covariance allows you to build a single delegate that can point to methods returning class

types related by classical inheritance:

class Program

{