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

// Using explicit implementation to handle member name clash.

void IPrintable.Draw()

{ // Draw to printer ...

}

void IDrawable.Draw()

{ // Draw to screen ...

}

public void Print()

{ // Print ...

}

public int GetNumberOfSides()

{ return 4; }

}

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So at this point, you hopefully feel more comfortable with the process of defining and imple-

menting custom interfaces using the syntax of C#. To be honest, interface-based programming can

take awhile to get comfortable with, so if you are in fact still scratching your head just a bit, this is a

perfectly normal reaction.

Do be aware, however, that interfaces are a fundamental aspect of the .NET Framework.

Regardless of the type of application you are developing (web-based, desktop GUIs, data access

libraries, etc.), working with interfaces will be part of the process. To summarize the story thus far,

remember that interfaces can be extremely useful when

• You have a single hierarchy where only a subset of the derived types support a common

behavior.

• You need to model a common behavior that is found across multiple hierarchies with no

common parent class beyond System.Object.

Now that you have drilled into the specifics of building and implementing custom interfaces,

the remainder of the chapter examines a number of predefined interfaces contained within the

.NET base class libraries.