所以我正在制作一个基于文本的RPG，我想一次遇到多个敌人。因此，我修改了确定是否将Monster类的对象填充到Monster类数组中并将对象bool设置为true的函数，如您在此处看到的那样：
Monster * Map::checkRandomEncounter()
{
Monster* monster = new Monster[3];
for (int i = 0; i < 3; i++)
{
int roll = Random(0, 20);
if (roll <= 5)
{
//No encounter
return 0;
}
else if (roll > 6 && roll < 10)
{
monster[i] = Monster();
monster[i].giveID("Orc", 10, 8, 200, 100, 1, "Short Sword", 2, 7);
monster[i].isFilled();
std::cout << "You encounter an Orc!" << std::endl;
std::cout << "Prepare for battle!" << std::endl;
std::cout << std::endl;
}
else if (roll >= 11 && roll <= 15)
{
monster[i] = Monster();
monster[i].giveID("Goblin", 6, 6, 100, 75, 0, "Dagger", 1, 5);
monster[i].isFilled();
std::cout << "You encounter a Goblin!" << std::endl;
std::cout << "Prepare for battle!" << std::endl;
std::cout << std::endl;
}
else if (roll >= 16 && roll <= 19)
{
monster[i] = Monster();
monster[i].giveID("Ogre", 20, 12, 500, 200, 2, "Club", 3, 8);
monster[i].isFilled();
std::cout << "You encounter an Ogre!" << std::endl;
std::cout << "Prepare for battle!" << std::endl;
std::cout << std::endl;
}
else if (roll == 20)
{
monster[i] = Monster();
monster[i].giveID("Orc Lord",
25,
15,
2000,
1000,
5,
"Two Handed Sword",
5,
20);
monster[i].isFilled();
std::cout << "You encounter an Orc Lord!" << std::endl;
std::cout << "Prepare for battle!" << std::endl;
std::cout << std::endl;
}
}
return monster;
}
上面的函数将在我的主函数中调用，如下所示：
int main()
{
srand(time(0));
Map gameMap;
Player mainPlayer;
mainPlayer.createClass();
//Beginn adventure
bool done = false;
while (done == false)
{
// Each Loop Cycle outputs player pos and selection menu
gameMap.printPlayerPos();
int selection = 1;
std::cout << "1) Move 2) Rest 3) View Stats 4) Quit: ";
std::cin >> selection;
Monster* monster = 0;
switch (selection)
{
case 1: // Move the player
gameMap.movePlayer();
if (gameMap.getPlayerXPos() == 2
&& gameMap.getPlayerYPos() == 3)
{
std::cout << "You see a store nearby !" << std::endl;
}
if (gameMap.getPlayerXPos() == 2
&& gameMap.getPlayerYPos() == 4)
{
Store store;
store.enter();
store.showInventory(mainPlayer);
}
//Check for a random encounter
//returns a null pointer if no encounter happened
monster = gameMap.checkRandomEncounter();
//'monster' not null, start battle script
if (monster != 0)
{
//Loop until a break statement
for (int i = 0; i < 3; i++)
{
//Display Hitpoints
mainPlayer.displayHitPoints();
monster[i].displayHitPoints();
std::cout << std::endl;
//Players turn to attack first
**bool runAway = mainPlayer.attack(monster, mainPlayer);** // Crash happening in this area
if (runAway) // Player flees
{
break;
}
if (monster[i].isDead())
{
mainPlayer.victory(monster->getXPReward(),
monster->getGoldReward());
mainPlayer.levelUp(mainPlayer);
}
break;
//Monster attacks
monster[i].attack(mainPlayer);
if (mainPlayer.isDead())
{
mainPlayer.gameOver();
done = true;
break;
}
}
//Pointer to Monster must destroy created instance of Monster
//to make sure that there is no Memory leak
}
delete monster;
monster = 0;
break;
case 2: // resting
mainPlayer.rest();
monster = gameMap.checkRandomEncounter();
//'monster' not null, start battle script
monster = gameMap.checkRandomEncounter();
//'monster' not null, start battle script
if (monster != 0)
{
//Loop until a break statement
for (int i = 0; i < 3; i++)
{
//Display Hitpoints
mainPlayer.displayHitPoints();
monster[i].displayHitPoints();
std::cout << std::endl;
//Players turn to attack first
bool runAway = mainPlayer.attack(monster, mainPlayer);
if (runAway) // Player flees
{
break;
}
if (monster[i].isDead())
{
mainPlayer.victory(monster->getXPReward(),
monster->getGoldReward());
mainPlayer.levelUp(mainPlayer);
}
break;
//Monster attacks
monster[i].attack(mainPlayer);
if (mainPlayer.isDead())
{
mainPlayer.gameOver();
done = true;
break;
}
}
//Pointer to Monster must destroy created instance of Monster
//to make sure that there is no Memory leak
}
delete monster;
monster = 0;
break;
case 3: // viewing stats
mainPlayer.viewStats();
break;
case 4: // quitting
done = true;
break;
}
}
return 0;
}
最后是拼图，这是玩家攻击怪物的功能：
bool Player::attack(Monster Monster[], Player& Player)
{
int ArmorBefore = 0;
int Roll = 0;
int selection = 1;
int i;
if (Monster[0].isFilled() == true)
{
i = 0;
}
else if (Monster[1].isFilled() == true)
{
i = 1;
}
else if (Monster[2].isFilled() == true)
{
i = 2;
}
if (Monster[i].isFilled() == true)
{
std::cout << "1) Attack 2) Run 3) Cast Spell 4) Use Item: ";
std::cin >> selection;
std::cout << std::endl;
switch (selection)
{
case 1: // Player fights
std::cout << " You attack an " << Monster[i].getName()
<< " with a " << mWeapon.mName << std::endl;
if (Random(0, 20) < mAccuracy) // Player hits Monster
{
int damage = Random(mWeapon.mDamageRange);
int totalDamage = damage - Monster[i].getArmor();
if (totalDamage <= 0) // Armor is equal or higher than player atk
{
std::cout << "Your attack failed to penetrate "
<< Monster[i].getName() << "'s armor !"
<< std::endl;
return false;
}
else // Attack is higher than Monsters armor
{
std::cout << "You hit " << Monster[i].getName()
<< " for " << totalDamage << " damage !"
<< std::endl;
// Subtract dmg from Monsters hp
Monster[i].takeDamage(totalDamage);
return false;
}
}
else // Player Misses
{
std::cout << "You miss !" << std::endl;
}
std::cout << std::endl;
return false;
break;
case 2: // Player runs with a 25% chance
Roll = Random(1, 4);
if (Roll == 1) // Success
{
std::cout << "You run away !" << std::endl;
return true; // <- Return out of the function
}
else
{
std::cout << "You failed to escape !" << std::endl;
return false;
}
case 3: // Casting Spell
{
int SpellSelect;
// Spells for the Fighter
if (Player.mClassName == "Fighter")
{
std::cout << std::endl;
std::cout << "1) Shield 2) Mighty Blow: ";
std::cin >> SpellSelect;
if (SpellSelect == 1)
{
if (Player.mMagicPoints >= 10) // checks for player mana
{
std::cout << "You cast a mighty shield!"
<< std::endl;
ArmorBefore = Player.mArmor;
Player.shield(Player);
Player.mMagicPoints -= 10;
}
else
{
std::cout << "Not enough Mana" << std::endl;
break;
}
}
else
{
if (Player.mMagicPoints >= 5) // casting Mighty Blow
{
int damage = Random(mMightyBlow.mDamageRange);
std::cout
<< "You strike with all your might ! and Deal "
<< damage << " damage !" << std::endl;
Monster[i].takeDamage(damage);
Player.mMagicPoints -= 5;
return false;
}
else
{
std::cout << "Not enough Mana" << std::endl;
return false;
}
}
}
//Spells for the Wizard
else if (Player.mClassName == "Wizard")
{
std::cout << "1) Fireball";
std::cin >> SpellSelect;
if (Player.mMagicPoints >= 45)
{
int damage = Random(mFireball.mDamageRange);
std::cout << "You cast a Fireball and deal " << damage
<< " damage !" << std::endl;
Monster[i].takeDamage(damage);
Player.mMagicPoints -= 45;
return false;
}
else
{
std::cout << "Not enough Mana" << std::endl;
return false;
}
}
// Spells for the Cleric
else if (Player.mClassName == "Cleric")
{
std::cout << "1) Magic Missile";
std::cin >> SpellSelect;
if (Player.mMagicPoints >= 35)
{
int damage = Random(mMagicMissile.mDamageRange);
std::cout << "You cast a Magic Missile and deal "
<< damage << " damage !" << std::endl;
Monster[i].takeDamage(damage);
Player.mMagicPoints -= 35;
}
else
{
std::cout << "Not enough Mana" << std::endl;
return false;
}
}
}
case 4: // using Item
int invSlot;
std::cout << "1) HP Potion: ";
std::cin >> invSlot;
if (invSlot == 1) // Potion slot
{
if (mHPot.mAmount.size() > 0)
{
std::cout << "You used a Potion and healed for 5 HP !"
<< std::endl;
int currentSize = mHPot.mAmount.size();
mHPot.mAmount.resize(currentSize - 1);
Player.mHitPoints += 5;
if (Player.mHitPoints > Player.mMaxHitPoints)
{
Player.mHitPoints = Player.mMaxHitPoints;
}
return false;
}
else
{
std::cout << "You have no Potions!" << std::endl;
return false;
}
}
else // wrong slot
{
std::cout << "No Item found!" << std::endl;
return false;
}
}
// Clearing stat boosts
if (Player.shield(Player) == true)
{
Player.mArmor = ArmorBefore;
}
}
return false;
}
当我运行游戏时，有时会遇到问题，即在阵列的插槽中填充怪物后，将不会触发任何战斗。而且如果要打一场战斗，我每次都会崩溃，并显示错误报告，内容为：
_CrtlValidHeadPointer（block）
我想我的指针不能正常工作...。但是由于我是初学者，所以我几乎陷于困境。我非常感谢您的启发：）
答案 0 :(得分：3)
这个地方可能会引起未定义的行为并崩溃：
int i;
if (Monster[0].isFilled() == true)
{
i = 0;
}
else if (Monster[1].isFilled() == true)
{
i = 1;
}
else if (Monster[2].isFilled() == true)
{
i = 2;
}
/*else // one of solutions
break;*/
//"i" can be unset! and can have any value from INT_MIN to INT_MAX!
if (Monster[i].isFilled() == true) //potentially index over array
{
此外，内存管理还存在内存泄漏和未定义的行为：
Monster* monster = new Monster[3];
...
delete monster
必须为delete [] monster
但是建议使用智能指针，向量，数组等进行内存管理