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// This class derives from System.Object and

// implements a single interface.

public class Pencil : IPointy

{...}

// This class also derives from System.Object

// and implements a single interface.

public class SwitchBlade : object, IPointy

{...}

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// This class derives from a custom base class

// and implements a single interface.

public class Fork : Utensil, IPointy

{...}

// This struct implicitly derives from System.ValueType and

// implements two interfaces.

public struct Arrow : IClonable, IPointy

{...}

Understand that implementing an interface is an all-or-nothing proposition. The supporting

type is not able to selectively choose which members it will implement. Given that the IPointy

interface defines a single read-only property, this is not too much of a burden.

However, if you are implementing an interface that defines ten members (such as the

IDbConnection interface seen earlier), the type is now responsible for fleshing out the details of

all ten abstract entities.

For this example, insert a new class type named Triangle which “is-a” Shape and supports

IPointy: