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SenthilNathan CAlagan

Joined: Jun 21, 2001
Posts: 4
Sub class reference can be assigned to super class reference.
But super class reference cannot be assigned to sub class reference(without explicit casting).Why it is so?
Can anyone explain me in detail?
Marilyn de Queiroz

Joined: Jul 22, 2000
Posts: 9058
The Subclass object ALWAYS is a Superclass object by definition. However, the reverse is not true.
For example, Dog "is a" Animal, but Animal is NOT always a Dog.

"Yesterday is history, tomorrow is a mystery, and today is a gift; that's why they call it the present." Eleanor Roosevelt
I agree. Here's the link:
subject: inheritance
It's not a secret anymore!