How do I call a function in a parent object? (C++) [closed] - c++

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Using the example below, I would like to call the function printTop() from my 'Bottom' object. It seems perhaps I could use a pointer to the parent object?
class Bottom {
public:
void printBottom(){std::cout << "print bottom";};
};
class Top {
public:
void printTop(){std::cout << "print top";};
private:
Bottom bottom;
};
Thanks.

Answer 1

If this is truly where your heart is at, it can be done (doesn't mean i'd advocate it):
class Top;
class Bottom {
public:
Bottom( const Top& topLevelObj ) : _topLevelObj(topLevelObj) { }
void printBottom() const {std::cout << "print bottom";};
void printTop() const;
private:
const Top& _topLevelObj;
};
class Top {
public:
Top() : _bottom(*this) {}
void printTop() const {std::cout << "print top";};
private:
Bottom _bottom;
};
void Bottom::printTop() const { _topLevelObj.printTop(); }

Answer 2

Firstly your code will not execute due to an error in your code, figure it out.
Secondly, you cannot call function printTop() from your Bottom object because you have no access to printTop() from the Bottom class.
You could maybe rewrite the code in this way:
class Top {
public:
void printTop(){ std::cout << "print top"; }
};
class Bottom {
public:
void printBottom(){ std::cout << "print bottom"; }
Top top;
};
int main()
{
Bottom B;
B.top.printTop();
return 0;
}