C# in Depth

Extension methodsThis chapter covers■■■Writing extension methodsCalling extension methodsMethod chaining■ Extension methods in .NET 3.5■Other uses for extension methodsI’m not a fan of inheritance. Or rather, I’m not a fan of a number of places whereinheritance has been used in code that I’ve maintained, or class libraries I’veworked with. As with so many things, it’s powerful when used properly, but it’s got adesign overhead to it that is often overlooked and can become painful over time.It’s sometimes used as a way of adding extra behavior and functionality to a class,even when no real information is being added about the object—where nothing isbeing specialized.Sometimes that’s appropriate—if objects of the new type should carry aroundthe details of the extra behavior—but often it’s not. Indeed, often it’s just not possibleto use inheritance in this way in the first place—if you’re working with a valuetype, a sealed class, or an interface. The alternative is usually to write a bunch ofstatic methods, most of which take an instance of the type in question as at least255Licensed to Rhona Hadida