Can't access derived class members?

[Anomaly]

class A {
public:
  double memberA;
}

class B : public A {
public:
  double memberB
}

B *bclass;
bclass = new B;
bclass->memberB = 1;  <--- ERROR: 'memberB': is not a member of 'A'

I can access public members of base class from outside of class, but not derived class members. I would like to know why?

Thanks

[Xenakios]

The code as you've written it in your forum post compiles just fine. (After fixing the syntax errors.)

However, if you changed this :

B *bclass;

to this :

A* bclass;

You will get the error you mentioned and it's completely normal and expected. C++ is a statically typed language, so if you have a pointer to class A, you will not be able to access members of class B (directly), even if B derives from A.

What you could do is to cast your pointer :

((B*)bclass)->memberB = 1;

But if you find yourself doing that a lot, your code design probably isn't correct.

[Anomaly]

Originally Posted by Xenakios

However, if you changed this :

B *bclass;

to this :

A* bclass;

I feel stupid now! This was the actual problem with my code. I was accidentally pointing to base class instead of derived class. Thanks!