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

// Calls base class implementation!

cir.Draw();

Console.ReadLine();

}

Figure 6-10.

Hmm . . . something is not quite right.

Clearly, this is not a very intelligent design for the current hierarchy. To force each child class to

override the Draw() method, you can define Draw() as an abstract method of the Shape class, which

by definition means you provide no default implementation whatsoever. To mark a method as

abstract in C#, you use the abstract keyword. Notice that abstract members do not provide any

implementation whatsoever:

C H A P T E R   6  

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U N D E R S TA N D I N G   I N H E R I TA N C E  A N D   P O LY M O R P H I S M

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