What are some examples of covariance in C#?

Can you explain covariance in C# with some examples?

Sure! Covariance allows you to use a more derived type than originally specified. For instance, if you have a method that returns a base class type, you can return a derived class type instead.

Can you give me a code example of covariance?

Absolutely! Here's a simple example:

IEnumerable<Dog> dogs = new List<Dog>();
IEnumerable<Animal> animals = dogs; // Covariance in action

What about contravariance? How does it differ?

Contravariance is the opposite; it allows you to use a less derived type. For example, if you have a method that takes a base class type, you can pass a derived class type instead.

Can you show me a contravariance example?

Sure! Here's a contravariance example:

Action<Animal> animalAction = (animal) => Console.WriteLine(animal.Name);
Action<Dog> dogAction = animalAction; // Contravariance in action