You can pass a reference-typed variable to a method as an output parameter, using the out keyword. This indicates that the parameter is an output method. For a reference type, this means that the method is expected to change the reference to point to a different object.
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| public static void FindBallPlayingDog(out Dog fav){ fav = null; foreach (Dog d in AllDogs) { if (d.Motto.Contains("ball")) fav = d; }} |
When calling the method, we need to include the out keyword as a parameter modifier:
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| Dog kirby = new Dog("Kirby");kirby.Motto = "Love chasing balls";Dog jack = new Dog("Jack");jack.Motto = "Sneak away when possible";Dog fav = jack;Dog.FindBallPlayingDog(out fav); // Fav is now Kirby |