class B{
private:
void DoSomething();
}
class W{
private:
class D: public B{
}
D d;
}
Can I call private member function in base class of D in the scope of class W?
views:
88answers:
3
+5
A:
Nope. You can never call a private member function from anywhere except the class that owns it. If you want derived classes to be able to access it, declare it protected instead.
You can also declare D to be a 'friend' of class B; that would allow D to access B.DoSomething(). However, this approach is usually frowned upon.
Aric TenEyck
2009-07-15 03:05:18
If DoSomething() is public. It seems that I cannot call it in the scope of W , right?
Jinx
2009-07-15 03:09:55
If you declare it as public you'll be able to access it from instances of B or instances of any class that extends B. But it has to be from an instance of the class:B b = new B(); b.DoSomething(). You can't just access it directly from W.
MadMurf
2009-07-15 03:23:14
+1
A:
The function DoSomething can be accessed outside the class only if it is declared as public or private. Besides as mentioned above by Aric, the inherited class can become a friend to achieve the same.
The alternative approach would be to declare/define the function as virtual and do not define the virtual definition for the sub/inherited class. Doing this, will call the function definition for the base class.
Roopesh Majeti
2009-07-15 03:13:47
A small correction in the the first line [ of my answer ], i mentioned it as "declared as public or private". It should be "public or protected"
Roopesh Majeti
2009-07-15 03:15:02
@Roopesh you can edit the answer to correct it rather than leaving a comment. Just so you know StackOverflow provides the option.
MadMurf
2009-07-15 03:18:37
+1
A:
No, if you use the protected keyword then you can. The fact that it is a nested class is irrelevant.
hacim
2009-07-15 03:30:49