Use the private variable of the superclass with friend

Question

I have a class A with a private variable a. Class B is a subclass of A. In class B_Test, I would like to wrtite something like "B b; b.a;", I put friend class C in both Class A and Class B but it still no works.

Any idea? Thank you.

(Sorry I make a mistake in my code when I post this question. It is solved now). Rod_Algonquin is right. Thank you.)

The private variable a is defined in A, B inherit A. Can I still use B.a with friend? — xieziban, May 29 '14 at 22:57
@Rod_Algonquin Sure you can. http://coliru.stacked-crooked.com/a/74d909f443247fa4 — aschepler, May 29 '14 at 23:36

score 3 · Accepted Answer · answered May 29 '14 at 22:47

3

Private members do not get inherited. If you want to access that member in the inherited class, you need to use protected modifier.

answered May 29 '14 at 22:47

Andro

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Thanks Andro. So it is different from Java? Let's say class A has a virtual public function to return a, in this case what will happen to class B? – xieziban May 29 '14 at 22:54
@xieziban Class A will be a polymorphic class and class B can now be casted to Class A but class A cant be downcasted – Rod_Algonquin May 29 '14 at 23:05
@Rod_Algonquin: I'm not certain that answered the right question – Mooing Duck May 29 '14 at 23:26

Use the private variable of the superclass with friend

1 Answers1