c++ - 使用 std::vector 时发生访问冲突

Question

我收到以下错误:

• TBG.exe 中 0x012a4bd9 处的未处理异常:0xC0000005:访问冲突读取位置 0x0000002c。

指向vector.h的size()方法。使用这种方法时似乎会发生:

void Player::printInventory(){
    if(inventory.size() != 0){
        for(unsigned int i=0; i<inventory.size(); i++){
            cout<<inventory[i] << endl;
        }
    }
}

---

完整代码:

播放器.h:

#pragma once
#include <vector>
#include <memory>

using namespace std;

class Player
{
private:
    int health;
    string name;
    vector<int> inventory;

public:
    Player(void);
    Player(string);
    ~Player(void);
    void changeHealth(int);
    void addToInventory(int);
    void removeFromInventory(int);
    void printInventory();
};

播放器.cpp:

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

Player::Player(void)
{
    health = 20;
}

Player::Player(string newName)
{
    name = newName;
    health = 20;
}

Player::~Player(void)
{
}

void Player::changeHealth(int amount){
    health += amount;
}

/*void Player::addToInventory(int item){
    inventory.push_back(item);
}

void Player::removeFromInventory(int itemID){

    for(unsigned int i=0; i<inventory.size(); i++){
        if(inventory[i] == itemID)
            inventory.erase(inventory.begin()+i);
    }

}*/

void Player::printInventory(){
    if(!inventory.empty()){
        for(unsigned int i=0; i<inventory.size(); i++){
            cout<<inventory[i] << endl;
        }
    }
}

主要内容:

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

World world;

void main(){

    unique_ptr<Player> player(new Player("Ted"));
    world.setPlayer(move(player));
    int selection = 0, inventoryOption = 0, exitOption = 0;

    do{
        inventoryOption = 0;
        exitOption = inventoryOption + 1;

        cout<< inventoryOption <<". View Inventory"<<endl;
        cout<< exitOption <<". Quit game";

        cin>>selection;

        if(selection == inventoryOption){
            player->printInventory();
        }
        else{
        }


    }while(selection != exitOption);

}

请原谅困惑，此代码是从具有相同错误的先前代码中删除的。

Answer 1

您正在移动unique_ptr，使其不再指向新播放器，然后您正在使用它:

world.setPlayer(move(player));

...

player->printInventory();

不要仅仅为了编译代码而使用move；使用 shared_ptr 这样您就可以拥有多个指向该对象的指针。