June 23, 2002 - Defining Polymorphism

Yehuda Shiran June 23, 2002
Defining Polymorphism
Tips: June 2002

Yehuda Shiran, Ph.D.
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Polymorphism is considered one of the three cornerstones of object oriented programming languages, besides encapsulation and inheritance. The words "poly" (many) and "morph" (shape) indicate that polymorphism is about supporting many shapes. Polymorphism is based on polymorphic methods. A polymorphic method behaves differently, depending on the object type it is called with. On the outside, all calls to a polymorphic method look identical. The method identifies by itself the type of the object and behaves accordingly. In this way, the nuts and bolts of the code are hidden from you. You just call the object with the operation (method) that you need to apply to the object. You don't care what type the object is of, or how to adapt the operation to the type. The change in behavior is hidden inside the method.

To learn more about JScript .NET, go to Column 111, JScript .NET, Part V: Polymorphism.