如何从不同的类中获取一个函数来调用在 Main 中声明的对象？

Question

I am making a tictactoe game and would like the function for a player turn to access objects i declared in main and other functions how could i do that?

void Player1Turn::player1Turn() {

char num;
cin >> num;

if (num == '1')
{
    board[0][0] = { xo1 };
}

For example how could i get board to change the values of gameboard?

int main()
{

    Setup setup;
    Gameboard gameboard;
    Player1Turn player1turn;

    setup.setup();
    gameboard.printBoard();
    player1turn.player1Turn();

    return 0;
}

If this is not enough code I could provide more

Answer 1

You could add a reference to the specific Gameboard as an argument to the player1Turn member function. So, assuming your Gameboard class has a board[][] member, it would look something like this:

void Player1Turn::player1Turn(Gameboard& gb)
{
    char num;
    cin >> num;

    if (num == '1')
    {
        gb.board[0][0] = { xo1 }; // Exact code will depend on your "Gameboard" definition.
    }
}

And your call from main would be like this:

int main()
{
    Setup setup;
    Gameboard gameboard;
    Player1Turn player1turn;

    setup.setup();
    gameboard.printBoard();
    player1turn.player1Turn(gameboard); // Argument is the Gameboard to work on.

    return 0;
}

There are many other ways to achieve this, though, but I can't really suggest anything more/better without more details of your various classes. Another way, as suggested in the comment by Nico Schertler , would be to have the reference to Gameboard as a "data" member in the Player1Turn class and pass the reference in its constructor.

Feel free to ask for further clarification and/or explanation.

PS: Your use of the three names, "Player1Turn" (for the class), "player1Turn" (for the member function) and "player1turn" (for the specific object in main ) is extremely prone to typing errors! You should seriously consider a better naming scheme!!