OOP - A member function of one class inside a member function of another class

Question

A member function of one class within the member function of another class.

Hello. I try that the content of the member function method() ; of class B is printed in the member function method() ; of class A , but I have not succeeded. When trying to compile I get errors.

Do you have any suggestions to fix this issue?

#include <iostream>
#include <string>

using namespace std;

class A { 
public:
    void method();
};

class B { 
public:
    int n = 6;
    int x;
    string** plantas;
    string cantidad, m_nombre, m_familia, m_genero, m_luz, m_riego, m_fertilizante;
    static void method();
};

void A::method(){
    cout << "Inicio" << endl;
    B::method();
    cout << "Final" << endl;
}

void B::method(){
    cout << "\n \t ¿Cuántas plantas registrarás?" << endl;
    getline(cin, cantidad);
    x = stoi(cantidad);
    plantas = new string * [n];

    cin.ignore();
    for (int i = 0; i < x; i++) {
        plantas[i] = new string[n];
        cout << "\t Nombre: ";
        getline(cin, m_nombre);
        cout << "\t Familia: ";
        getline(cin, m_familia);
        cout << "\t Genéro: ";
        getline(cin, m_genero);
        cout << "\t Ubicación (Luz/Sombra): ";
        getline(cin, m_luz);
        cout << "\t Periodo de riego: ";
        getline(cin, m_riego);
        cout << "\t Periodo de fertilización: ";
        getline(cin, m_fertilizante);
        plantas[i][0] = m_nombre;
        plantas[i][1] = m_familia;
        plantas[i][2] = m_genero;
        plantas[i][3] = m_luz;
        plantas[i][4] = m_riego;
        plantas[i][5] = m_fertilizante;
    }

    for (int i = 0; i < x; i++) {
        delete[] plantas[i];
    }

    delete[] plantas;

    system("pause");
}

int main(){
    A a;
    a.method();
    
    return 0;
}

Answer 1

Static methods refer to the class as such; non-static methods act on the instance of the class. That's why non-static member functions have an implicit (invisible) first parameter: the instance on which they act.

So with non-static methods, you can access non-static members (both fields and functions) and static members (again both), because you have an instance and you can access the class (global) properties.

With static methods, you don't have an instance to work on, so you only can use the static members (both fields and functions).

In your code, you try to access your non-static member B::plantas inside the static member function B::method() . This doesn't work. Either you make B::plantas static as well, or you make B::method() non-static and create an instance of B to work with.