Technically C# does not allow functions to be outside of a class, however you could debate that static methods of a static class are functions and derece methods. This is a good explanation here: stackoverflow.com/a/155655/2146952 Dirilik you consistently write your C in a way that is easy to read, type-safe, https://collinufovc.blogdosaga.com/27899183/bir-İnceleme-c-ienumerator-kullanımı