Say I have
Class Base {}
Class Child: public Base {
void alert() { printf("alert"); }
}
How do I call alert() with type Base?
Base *p = new Child();
p->alert() // error, Base does not have alert method
I've tried this but doesn't work as well.
p->Child::alert() // error, Base does not have alert method
I can fix the problem if I move alert() to Base of course but I don't want Base to have alert() so it won't pass on to other children.
"How do I call alert() with type Base?"
To do so make Base an abstract class
class Base {
virtual void alert() = 0; // <<<<<
}
class Child: public Base {
void alert() { printf("alert"); }
}
If you really want or need to avoid providing alert() in your base class you can use a static_cast<Child*>
static_cast<Child*>(p)->alert();
Base to avoid this. Casting correctly is another option (see my update).When you have a child class object which is having a base class reference type you cannot call the methods which are only present in child class you can only call the methods which are common to both classes.The base class function is over-ridden in this case unless we use super.
Class->classandPublic->public.