How to access from 1 class to other class struct-CodePudding

I'm a beginner and trying to learn coding. So please excuse if my question is stupid. I have these 2 classes and I want the class Store to have access a data from struct Stock in class Toys. I'm not sure how can I do this?

#include <vector>
#include <string>
#include <iostream>

class Toys {
public:
    struct Stock
    {
        int x;
        Stock(int value)
            :x(value) {}
    };
};

class Store {
public:
    Toys myToy(int count) {
        _count = count;
    }
    Toys* myStore;
    //What do I need to do to bind a struct Stock from class Toy here?
private:
    int _count;
};

int main()
{
    Store myStore;
    int x;
    std::vector<Toys::Stock> stocks;
    std::cout << "Enter the availability for Water Gun.\n";
    std::cin >> x;
    for (int i = 0; i <= x; i  ) {
        stocks.push_back(i);
        std::cout << stocks[i].x << std::endl;
    }
//Later I want to pull vector stocks from class Store here.
    return 0;
}

CodePudding user response：

You can use Store as friend class of Toys which enables you to use data members of Toys class in Store class Try it !

CodePudding user response：

Normally you'd have to add a friend declaration saying that you want to access private data from a particular class but since in your given example Stock is a struct and since you've used public access specifier inside Toys while declaring Stock, there is no need for the friend declaration here.

This means, you can create an instance of type Toys::Stock inside Store without having any friend declaration as shown below:

class Store {
public:
    
    Toys* myStore;
    
    Toys::Stock s1; // a data member named `s1` of type Toys::Stock
  
    Toys::Stock* ptr; //a data member named `ptr` of type Toys::Stock*
    int _count;
};