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// This interface defines the behavior of "having points."

public interface IPointy

{

// Implicitly public and abstract.

byte GetNumberOfPoints();

}

Notice that when you define interface members, you do not define an implementation scope

for the member in question. Interfaces are pure protocol, and therefore never define an implemen-

tation (that is up to the supporting class or structure). Therefore, the following version of IPointy

would result in various compiler errors:

// Ack! Errors abound!

public interface IPointy

{

// Error! Interfaces cannot have fields!

public int numbOfPoints;

// Error! Interfaces do not have constructors!

public IPointy() { numbOfPoints = 0;};

// Error! Interfaces don't provide an implementation!

byte GetNumberOfPoints() { return numbOfPoints; }

}

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In any case, this initial IPointy interface defines a single method. However, .NET interface

types are also able to define any number of property prototypes. For example, you could create the

IPointy interface to use a read-only property rather than a traditional accessor method: