14.1. Defining Custom Namespaces

Before diving into the details of assembly deployment and configuration, you must know how to create custom .NET namespaces. Up to this point in the text, you've been building small test programs that leverage existing namespaces in the .NET universe (System in particular). However, when you build your own custom applications, it can be very helpful to group your related types into custom namespaces. In C#, this is accomplished using the namespace keyword. Explicitly defining custom namespaces is even more important when creating .NET *.dll assemblies, as other developers will need to import your custom namespaces in order to use your types.

To investigate the issues firsthand, begin by creating a new Console Application named CustomNamespaces. Now, assume you are developing a collection of geometric classes named Square, Circle, and Hexagon. Given their similarities, you would like to group them all together into a unique namespace within the CustomNamespaces.exe assembly called MyShapes. You have two basic approaches. First, you can choose to define all classes in a single C# file (ShapesLib.cs) as follows: