Custom Namespaces in .NET

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 common custom namespace.You have two basic approaches. First, you may choose to define each class within a single file (shapeslib.cs) as follows:

// shapeslib.cs

using System;

namespace MyShapes

{

// Circle class.

class Circle{ /* Interesting methods... */ }

// Hexagon class.

class Hexagon{ /* More interesting methods... */ }

// Square class.

class Square{ /* Even more interesting methods... */ }

}

Notice how the MyShapes namespace acts as the conceptual “container” of these types. Alternatively,

you can split a single namespace into multiple C# files. To do so, simply wrap the given class

definitions in the same namespace:

// circle.cs

using System;

namespace MyShapes

{

// Circle class.

class Circle{ }

}

// hexagon.cs

using System;

namespace MyShapes

{

// Hexagon class.

class Hexagon{ }

}

// square.cs

using System;

namespace MyShapes

{

// Square class.

class Square{ }

}

As you already know, when another namespace wishes to use objects within a distinct namespace,the using keyword can be used as follows:

// Make use of types defined the MyShape namespace.

using System;

using MyShapes;

namespace MyApp

{

 class ShapeTester

  {

   static void Main(string[] args)

   {

    Hexagon h = new Hexagon();

    Circle c = new Circle();

    Square s = new Square();

   }

  }

}