我正在尝试学习 C++ OOP,我编写了以下代码:
main.cpp
#include <iostream>
#include <string>
#include "monster.h"
using namespace std;
int main(int argc, char** argv) {
Monster monster("Wizard",150,50);
Monster monster2("Gorgoyle",450,15);
cout << monster2.getHealth() << endl;
monster.attack(monster2);
cout << monster2.getHealth() << endl;
}
怪物.h
#ifndef MONSTER_H
#define MONSTER_H
#include <iostream>
#include <string>
using namespace std;
class Monster
{
public:
Monster(string name_, int health_, int damage_);
~Monster();
int attack(Monster opponet);
int getHealth();
string name;
int damage;
int health = 0;
int getDamage();
void setHealth(int health_);
void setDamage(int damage_);
void setName(string name);
void doDamageToOpponent(Monster opponent);
string getName();
};
#endif
怪物.cpp
#include "monster.h"
Monster::Monster(string name_, int health_, int damage_) {
health = health_;
setDamage(damage_);
setName(name_);
}
Monster::~Monster() { }
int Monster::attack(Monster opponent) {
doDamageToOpponent(opponent);
}
void Monster::doDamageToOpponent(Monster opponent) {
int newHealth = opponent.getHealth() - this->getDamage();
opponent.setHealth(newHealth);
}
int Monster::getHealth() {
return health;
}
int Monster::getDamage() {
return damage;
}
void Monster::setHealth(int health_) {
health = health_;
}
void Monster::setDamage(int damage_) {
this->damage = damage_;
}
void Monster::setName(string name_) {
this->name = name_;
}
string Monster::getName() {
return name;
}
现在我的问题是,当我运行这段代码时,我希望 monster2 对象有 400 点生命值,但它仍然是 450 :S
必须在这里做什么才能做到这一点?我注意到它在 doDamageToOppoenet 中可以是 400,但是当它离开那个 block 时,它仍然是 450。请帮助我!谢谢。
最佳答案
您正在按值传递对象:
void Monster::doDamageToOpponent(Monster opponent) <- This should be by reference
int Monster::attack(Monster opponent) <- idem
这意味着:您正在创建 Monster
对象的新拷贝,您打算在调用的函数中对其造成伤害,然后实际处理该拷贝的伤害但留下原始 < strong>旧的对象,其值未被修改。
以下签名可以代替:
void Monster::doDamageToOpponent(Monster& opponent)
int Monster::attack(Monster& opponent)
如果您想了解更多相关信息,请继续阅读:Passing stuff by reference和 Passing stuff by value
关于C++面向对象的问题,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/26046136/