#590 – Optional Parameters in Constructors

You’ll typically see optional parameters in methods.  But you can also define an optional parameter in a constructor:

        public string Name { get; set; }
        public int Age { get; set; }
        public string FavoriteToy { get; set; }
        public Dog Father { get; set; }
        public Dog Mother { get; set; }

        public Dog(string name, int age = 1, string favToy = "Bone",
            Dog father = null, Dog mother = null)
        {
            Name = name;
            Age = age;
            FavoriteToy = favToy;
            Father = father;
            Mother = mother;
        }

            Dog kirby = new Dog("Kirby", 15, "Ball");
            Dog sonOfKirby = new Dog("Ferbie", 2, "Frisbee", kirby);

Optional parameters in constructors avoid the need to chain constructors.