Accelerated C# 2010

Chapter 14. Extension Methods

Using extension methods, you can declare methods that appear to augment the public interface, or contract, of a type. At first glance, they may appear to provide a way to extend classes that are not meant to be extended. However, it's very important to note that extension methods cannot break encapsulation. That's because they're not really instance methods at all and thus cannot crack the shell of encapsulation on the type they are extending.

Introduction to Extension Methods

As previously mentioned, extension methods make it appear that you can modify the public interface of any type. Let's take a quick look at a small example showing extension methods in action:

using System; namespace ExtensionMethodDemo { public ...