我制作了一个小店主程序，允许玩家从该店主那里购买物品并将物品存储在玩家物品栏中。我是第一次使用 OOP 技术，遇到了一个无法解决的问题。
我遇到的问题是在"店主.cpp"，"购买物品"中，物品没有添加到玩家库存中。我正在做的函数调用有问题。但是，如果我在main中调用"Player.AddItem(("，它可以正常工作。根据我的理解，我组织代码的方式是正确的吗？我觉得它是最具可读性的——至少对我来说是这样——尽管你可以随意说不是。
这是我到目前为止的代码。很抱歉代码很长，我不确定您可以在此处粘贴的数量是否有限制，但我认为最好全部显示。
提前非常感谢你。
主要
// Shop.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include "Player.h"
#include "ShopKeeper.h"
#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
int main()
{
Player player; //The player
ShopKeeper shopKeeper; //The shop keeper
int responce; //Menu navigation
std::cout << "Greetings " << player.GetName() << ". Feel free to browse my wares." << "n";
std::cout << "1: Purchase Items. 2: Sell Items. 3: List Your Items. 4: Show Gold. 5: Exit" << "n";
do
{
std::cin >> responce;
switch (responce)
{
case 1:
shopKeeper.PurchaseItem();
break;
case 2:
shopKeeper.SellItem();
break;
case 3:
player.ListInventory();
break;
case 4:
std::cout << "You have " << player.GetGold() << " gold coins." << "n";
break;
case 5:
std::cout << "Thank you for shopping." << "n";
break;
default:
std::cout << "Please enter valid data." << "n";
std::cout << "1: Purchase Items. 2: Sell Items. 3: List Your Items. 4: Show Gold. 5: Exit" << "n";
}
} while (responce != 5);
/*
//This works
player.AddItem("Mace", 30);
player.ListInventory();
std::cout << player.GetGold();
*/
//Keep window open
std::string barn;
std::cin >> barn;
return 0;
}
店主.h
#pragma once
#include <string>
class ShopKeeper
{
private:
public:
void PurchaseItem(); //Shop keeper has player buy items from them
void SellItem(); //Shop keeper sells item to player
ShopKeeper();
~ShopKeeper();
};
店主.cpp
#include "stdafx.h"
#include "ShopKeeper.h"
#include "Player.h"
#include <iostream>
//Player purchases item from shop keeper
void ShopKeeper::PurchaseItem()
{
Player player;
int responce = 0; //Menu navigation
std::cout << "1: Mace - 30 gold. 2: Bow - 50 gold. 3: Boots - 10 gold. 4: Bearskin - 75 gold. 5: Helmet - 25 gold." << "n";
do
{
std::cin >> responce;
switch (responce)
{
case 1:
player.AddItem("Mace", 30);
break;
case 2:
player.AddItem("Bow", 50);
break;
case 3:
player.AddItem("Boots", 10);
break;
case 4:
player.AddItem("Bearskin", 75);
break;
case 5:
player.AddItem("Helmet", 25);
break;
default:
std::cout << "Please enter valid data." << "n";
std::cout << "1: Mace - 30 gold. 2: Bow - 50 gold. 3: Boots - 10 gold. 4: Bearskin - 75 gold. 5: Helmet - 25 gold." << "n";
}
} while (responce > 5 || responce < 1);
}
//Shop keeper sells item to player
void ShopKeeper::SellItem()
{
Player player;
int responce = 0;
player.ListInventory();
switch (responce)
{
case 1:
player.SellItem(0, 20);
break;
case 2:
player.SellItem(1, 20);
break;
case 3:
player.SellItem(2, 20);
break;
case 4:
player.SellItem(3, 20);
break;
case 5:
player.SellItem(4, 20);
break;
default:
std::cout << "Please enter valid data." << "n";
player.ListInventory();
}
}
ShopKeeper::ShopKeeper()
{
}
ShopKeeper::~ShopKeeper()
{
}
玩家.h
#pragma once
#include <vector>
class Player
{
private:
const int maxNumbItems = 5; //Maximum number of items that inventory can store
int goldCoins = 150, //Amount of gold coins the player has
numbOfItems = 0; //Number of con-current items player holds
std::vector<std::string> inventory; //Players inventory
std::string name = "Gorrex"; //Players name
public:
std::string GetName(); //Get the players name
std::string AddItem(std::string item, int itemPrice); // Add item to players inventory
void Player::SellItem(int itemNum, int itemPrice); //Sell item
bool IsInventoryFull(); //Check to see if players inventory is full
int InventoryCapacity(); //Get capacity of inventory
int GetGold(); //Get players gold
void ListInventory();
Player();
~Player();
};
播放器.cpp
#include "stdafx.h"
#include "Player.h"
#include <iostream>
#include <ostream>
#include <string>
//Get the players name
std::string Player::GetName()
{
return name;
}
//Add item to players inventory
std::string Player::AddItem(std::string item, int itemPrice)
{
//Is players inventory not full?
if (IsInventoryFull())
{
std::cout << "Inventory is full.";
}
else
{
//Can player afford item?
if (goldCoins >= itemPrice)
{
goldCoins -= itemPrice;
numbOfItems++;
std::cout << "You have purchased " << item << "." << "n";
inventory.push_back(item); //Add item to inventory
return item;
}
//If player cant afford item
else
{
std::cout << "You cannot afford this item." << "n";
}
}
}
void Player::SellItem(int itemNum, int itemPrice)
{
char responce;
std::cout << "Are you sure you want to sell: " << inventory[itemNum] << "? 'y' - Yes. 'n' - No." << "n";
std::cin >> responce;
switch (responce)
{
case 'y':
numbOfItems++;
goldCoins += itemPrice;
inventory.erase(inventory.begin() + itemNum);
break;
case 'n':
std::cout << "That is ok." << "n";
break;
default:
std::cout << "Please enter correct data." << "n";
}
}
//Check to see if players inventory is full
bool Player::IsInventoryFull()
{
//If players inventory isnt full
if (numbOfItems < maxNumbItems)
{
return false;
}
//If players inventory is full
else
{
return true;
}
}
//Return size of players inventory
int Player::InventoryCapacity()
{
return inventory.size();
}
//Get the players gold
int Player::GetGold()
{
return goldCoins;
}
//List the players inventory
void Player::ListInventory()
{
int itemNumb = 0; //item number in menu
for (int i = 0; i < inventory.size(); i++)
{
itemNumb++;
std::cout << itemNumb << ": " << inventory[i] << "n";
}
/* //If inventory is empty
if (inventory.empty())
{
std::cout << "inventory is empty" << "n";
}*/
}
Player::Player()
{
}
Player::~Player()
{
}
在 Shopkeeper 中，您声明的是函数调用后消失的Player的本地实例：
void ShopKeeper::PurchaseItem()
{
Player player;
使PurchaseItem接受Player& player，而不是声明本地Player。
SellItem也是如此。您需要指定向谁销售。
然后在您的main中可以这样说：
switch (responce)
{
case 1:
shopKeeper.PurchaseItem(player);
break;
case 2:
shopKeeper.SellItem(player);
//...
ShopKeeper 中的Player是ShopKeeper的本地，与main Player无关。
您必须将Player传递给ShopKeeper方法。您有几种选择：在构造函数中传递它ShopKeeper或通过引用传递给方法：
取代
void ShopKeeper::PurchaseItem()
{
Player player;
// ...
由
void ShopKeeper::PurchaseItem(Player& player)
{
// ...
并称它
shopKeeper.PurchaseItem(player);