This print for content only-size & color not accurate 7" X 9-1/4" / casebound / malloy

// Multiple inheritance for interface types is a-okay.

public interface IDrawable

{

void Draw();

}

public interface IPrintable

{

void Print();

void Draw(); // <-- Note possible name clash here!

}

// Multiple interface inheritance. OK!

public interface IShape : IDrawable, IPrintable

{

int GetNumberOfSides();

}

Figure 9-9 illustrates the current interface hierarchy.

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Figure 9-9.

Unlike classes, interfaces can extend multiple interface types.

Now, the million dollar question is, if we have a class supporting IShape, how many methods

will it be required to implement? The answer: it depends. If we wish to provide a simple implemen-

tation of the Draw() method, we only need to provide three members, as shown in the following

Rectangle type:

class Rectangle : IShape

{

public int GetNumberOfSides()

{ return 4; }

public void Draw()

{ Console.WriteLine("Drawing..."); }

public void Print()

{ Console.WriteLine("Prining..."); }

}

If you would rather have specific implementations for each Draw() method (which in this case

would make the most sense), you can resolve the name clash using explicit interface implementa-

tion, as shown in the following Square type:

class Square : IShape

{