c++：OOP：如何在单独的 header 文件中更新数组？

Question

我是 c++ 的新手，正在尝试创建一个基本的迷宫游戏。目前，我正在尝试让玩家能够在迷宫中移动，其中玩家的移动功能会更新网格数组中的角色。网格数组在 Grid.h 中，播放器在 Player.h 中，我在每个文件中都包含了 headers，但它们仍然无法访问彼此的成员变量。我尝试使用 'extern'，但也没有用。

我的老师建议将 m_grid 数组发送给构造函数，但没有指定哪个构造函数或在任何情况下如何执行。任何帮助将不胜感激，谢谢。

Grid.h

#include <iostream>
#include "Player.h"

class Grid
{
public:
    Grid();
    ~Grid();
    void Print_grid();
    char m_grid[18][32] =
    {
        {"_______________________________"},
        {"|   _______  ____________     |"},
        {" @                            |"},
        {"|_  _____________   __________|"},
        {"|   |                         |"},
        {"| | |__  |  |       |   |     |"},
        {"| |      |  | |___  |   |  |  |"},
        {"| | _____|  | |      ___|  |  |"},
        {"| |           |     |      |  |"},
        {"| |_________         _____    |"},
        {"|                  _______  __|"},
        {"|_______________              |"},
        {"|_____    _______________|  __|"},
        {"|         |        _______    |"},
        {"|   |  ____________   ________|"},
        {"|   |     #                   |"},
        {"|   |  |      __|________     |"},
        {"|______|______________________|"}
    };
};

Player.h

#pragma once
#include "Grid.h"
#include "Enemy.h"

extern char y;
extern char x;
extern char m_grid[18][32];

class Player 
{
public:
    Player();
    ~Player();
    static const char avatar = '@';
    void Set_difficulty();
    void Move(int speed);
    int m_speed{ 0 };
    struct Vector2
    {
        int y{ 0 };
        int x{ 1 };

        int new_y{ 0 };
        int new_x{ 0 };
    };
    Vector2* playerPos = nullptr;

    int m_score{ 0 };
    int m_highscore{ 0 };
    void Print_score();

private:
    char m_difficulty = ' ';
};

Player.cpp

#include <iostream>
#include "Player.h"

Player::Player()
{
    m_grid[playerPos.y][playerPos.x] = avatar;
}

Player::~Player()
{
}

void Player::Set_difficulty()
{

    std::cout << "Pick your difficulty:\nH -> Hard\nN -> Normal\nE -> Easy\n\nInput : ";
    std::cin >> m_difficulty;

    if (m_difficulty == 'e' || m_difficulty == 'E')
    {
        m_speed = 3;
    }
    else if (m_difficulty == 'n' || m_difficulty == 'N')
    {
        m_speed = 2;
    }
    else
    {
        m_speed = 1;
    }

}

void Player::Move(int speed)
{
    if (GetAsyncKeyState(VK_DOWN))
    {
        if (m_grid[playerPos->y+1][playerPos->x] == ' ' || m_grid[playerPos->y + 1][playerPos->x] == '*') //if desired space is empty or has a coin
        {
            playerPos->new_y = playerPos->y + speed; //new player pos = current pos + speed
            m_grid[playerPos->y][playerPos->x] == ' '; //old space is now empty
        }
    }
    if (GetAsyncKeyState(VK_UP))
    {
        if (m_grid[playerPos->y-1][playerPos->x] == ' ' || m_grid[playerPos->y-1][playerPos->x] == '*')
        {
            playerPos->new_y = playerPos->y - speed;
            m_grid[playerPos->y][playerPos->x] == ' ';
        }
    }
    if (GetAsyncKeyState(VK_RIGHT))
    {
        if (m_grid[playerPos->y][playerPos->x+1]== ' ' || m_grid[playerPos->y][playerPos->x+1] == '*')
        {
            playerPos->new_x = playerPos->x + speed;
            m_grid[playerPos->y][playerPos->x] == ' ';
        }
    }
    if (GetAsyncKeyState(VK_LEFT))
    {
        if (m_grid[playerPos->y][playerPos->x-1] == ' ' || m_grid[playerPos->y][playerPos->x-1] == '*')
        {
            playerPos->new_x = playerPos->x - speed;
            m_grid[playerPos->y][playerPos->x] == ' ';
        }
    }

}

void Player::Print_score()
{
}

Answer 1

首先：grid.h和player.h相互包含。应该避免这种情况，在这种情况下，grid.h 不需要 player.h.

实际问题：您的播放器没有可以使用的Grid对象。理想情况下，Grid 和 Player 应该是 Game class 的成员，并且对 Grid 对象的引用应该传递给 Player。所以它可以使用 Grid::m_grid。就像现在一样，您使用另一个仅声明为外部的 m_grid，因此没有真正的实例化。如果没有 Game class，这可以在 main() 中完成一个简单的练习，但是您需要声明一个 Grid 对象来访问它，如果玩家想要基于网格移动，则需要引用它。

c++：OOP：如何在单独的 header 文件中更新数组？

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