Factory is a design pattern that you can use when you don’t want client code creating objects directly, but you want to centralize object creation within another class. To get a new instance of an object, you call a method in the factory, which creates the object on your behalf.
In the example below, DogFactory.CreateDog is a factory method, which does the actual creation of a Dog object.
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| public sealed class DogFactory{ // Instance created when first referenced private static readonly DogFactory instance = new DogFactory(); // Prevent early instantiation due to beforefieldinit flag static DogFactory() { } // Prevent instantiation private DogFactory() { } public static DogFactory Instance { get { return instance; } } // Factory pattern - method for creating a dog public Dog CreateDog(string name, int age) { return new Dog(name, age); }} |
To create a Dog:
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| Dog myDog = DogFactory.Instance.CreateDog("Kirby", 15); |