我试图在这里找到答案，但是我发现没有任何作用。我这里有二十一点游戏。我的下一步是开始在游戏中添加资金余额和下注，但在此之前，我正在研究“重玩”选项。就目前而言，当玩家再次玩游戏时，他们的手牌与上一轮相同。我相信我需要调用一个析构函数来删除当前的手和牌组，然后重新开始。不幸的是，我不知道如何清理手并重新开始。我尝试在名为play的函数中调用此析构函数。在这里，如果玩家说他们想再次玩，我将删除手牌和套牌，然后将它们重建为主体。但是我已经尝试了“ deck.Deck ::〜Deck（）”和“ deck。〜Deck（）”两者，但都没有用。我将上传所有代码。如果有人有任何想法，请帮帮我。我知道析构函数应该在超出范围时由编译器调用，但是当游戏仍在进行且主程序仍在运行时，我该如何从新手和套牌开始？谢谢您的帮助。
这是我的头文件：
//blackjack.h A class to represent a deck of cards
#include <iostream>
#include <string>
class Card {
friend class Deck;
private:
int card_index; //card number 0 to 51
Card(int index) { card_index = index; } //made this private so user can't say card at index 100..can use it because of friend class
public:
Card() { card_index = 52; }
char suit() const;
char value() const;
std::string str() const;
int getValue(std::string c);
};
class Deck {
private:
Card cards[52];
int pos;
public:
Deck();
~Deck();
Card deal() { return cards[pos++]; };
void shuffle();
int size() const { return 52 - pos; };
};
class Hand {
friend class Deck;
friend class Card;
private:
int handSize;
int ctotal;
Card myCards[52];
public:
Hand() { handSize = 1; };
~Hand();
Hand(int n) { handSize = n; };
void dealFrom(Deck& d);
void reveal();
int total();
void hit(Deck& d);
};
std::ostream& operator<< (std::ostream& out, const Card& c);
这是我的实现文件：
//blackjack.cpp - Implementations of the Deck and Card classes
#include "blackjack.h"
#include <cstdlib>
char Card::suit() const {
static char suits[] = { 'H', 'S', 'D', 'C' };
//return card_index < 52 ? suits[card_index % 4] : 'X';
return suits[card_index % 4];
}
char Card::value() const {
static char values[] =
{ '2', '3', '4', '5', '6', '7', '8', '9', 'T', 'J', 'Q', 'K', 'A' };
//return card_index < 52 ? values[card_index / 4] : 'X';
return values[card_index / 4];
}
std::string Card::str() const {
std::string s;
s += value();
s += suit();
return s;
}
Deck::Deck() {
for (int i = 0; i < 52; i ++) {
cards[i] = Card(i);
}
pos = 0;
}
void Deck::shuffle() {
for (int i = 0; i < 52; i++) {
int j = rand() % 52;
Card tmp = cards[i];
cards[i] = cards[j];
cards[j] = tmp;
}
pos = 0;
}
std::ostream& operator<< (std::ostream& out, const Card& c) {
out << c.str();
return out;
}
int Card::getValue(std::string c) {
char v = c[0];
int val = v - '0';
if (val > 9) {
switch(v){
case 'T':
case 'J':
case 'Q':
case 'K':
val = 10;
break;
case 'A':
val = 11;
}
}
return val;
}
void Hand::dealFrom(Deck& d) {
for(int i = 0; i < handSize; i++)
myCards[i] = d.deal();
}
void Hand::reveal(){
for (int i = 0; i < handSize; i++)
std::cout << myCards[i] << " " << std::endl;
}
void Hand::hit(Deck& d) {
int index = handSize;
handSize++;
myCards[index] = d.deal();
}
int Hand::total() {
ctotal = 0; //reset card total
for (int i = 0; i < handSize; i ++) {
ctotal += myCards[i].getValue(myCards[i].str());
}
for (int i = 0; i < handSize; i ++) { //make ace 1 if over 21
if ( (myCards[i].getValue(myCards[i].str()) == 11) && ctotal > 21 )
ctotal = ctotal - 10;
}
return ctotal;
}
这是我的主程序：
#include "blackjack.h"
#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;
void play(bool& quitGame, bool& quit, Deck& deck, Hand& d,Hand & p) { //function to play again?
char ans;
cout << "\nPlay Again? y or n" << endl;
cin >> ans;
if (ans == 'y' || ans == 'Y') {
quitGame = false;
quit = false;
deck.Deck::~Deck(); //trying to delete the deck and hand objects before next game
d.Hand::~Hand();
p.Hand::~Hand();
//deck.~Deck();
//d.~Hand();
//p.~Hand();
} else if (ans == 'n' || ans == 'N')
quitGame = true;
else {
cout << "Incorrect response." << endl;
play(quitGame, quit, deck, d, p);
}
}
void reveal(Hand& d, Hand& p) { //function to reveal the hand
cout << "Your hand is: " << endl;
p.reveal();
cout << "Your total is: " << endl;
cout << p.total() << endl;
cout << endl;
cout << "Dealer's hand is: " << endl;
d.reveal();
cout << "Dealer's total is: " << endl;
cout << d.total() << endl;
}
void autoComplete(Hand& d, Hand& p, bool& quit, bool& quitGame, Deck& deck) { //function to check for blackjack and over 21
if (p.total() == 21 && d.total() == 21) {
cout << "You and dealer both hit blackjack. You tied." << endl;
quit = true;
play(quitGame, quit, deck, d, p);
} else if(p.total() == 21) {
cout << "Congratulations, you hit blackjack. You win!" << endl;
quit = true;
play(quitGame, quit, deck, d, p);
} else if(d.total() == 21) {
cout << "Sorry. Dealer hit blackjack. You lose." << endl;
quit = true;
play(quitGame, quit, deck, d, p);
} else if (p.total() > 21 && d.total() > 21) {
cout << "You and dealer both passed 21. Game is a tie." << endl;
quit = true;
play(quitGame, quit, deck, d, p);
} else if (p.total() > 21 && d.total() < 21) {
cout << "You passed 21. You lose.";
quit = true;
play(quitGame, quit, deck, d, p);
} else if (d.total() > 21 && p.total() < 21) {
cout << "Dealer passed 21. You win.";
quit = true;
play(quitGame, quit, deck, d, p);
}
}
int main() {
srand(time(0));
char response; // variable to hit or stand
bool quit = false; //variable to end the current round
bool quitGame = false; //variable to play game again
while (quitGame == false) { //while the player wants to continue playing
Deck deck; //create deck
Hand p(2); //player's hand
Hand d(2); //dealer's hand
deck.shuffle(); //shuffle deck
p.dealFrom(deck); //deal from deck
d.dealFrom(deck);
while (quit == false) { //while the round isn't over
reveal(d, p); //reveal the cards
autoComplete(d, p, quit, quitGame, deck); //check for blackjack and over 21
if(p.total() < 21 && quit == false) { //if games not over and player is under 21
cout << "Press 'h' to hit or 's' to stand." << endl;
cin >> response;
}
if (response == 'h') {
cout << " " << endl;
p.hit(deck);
if (d.total() < 17) //if the dealer hasn't hit 17, dealer hits deck
d.hit(deck);
}
if (response == 's') {
cout << " " << endl;
while (d.total() < 17){ //if the dealer hasn't hit 17, keep hitting deck
d.hit(deck);
}
if (d.total() < 21 && p.total() < 21) {
if (d.total() > p.total() && quit == false) { //if dealers total is higher than players total
reveal(d, p);
cout << "\nDealer wins!" << endl;
quit = true;
play(quitGame, quit, deck, d, p);
} else if (p.total() > d.total() && quit == false) { //if players total is higher than dealers total
reveal(d, p);
cout << "\nYou win!" << endl;
quit = true;
play(quitGame, quit, deck, d, p);
} else if (p.total() == d.total() && quit == false) { //if dealers total equals players total
reveal(d, p);
cout << "\nYou tied." << endl;
quit = true;
play(quitGame, quit, deck, d, p);
}
}
}
}
}
return 0;
}
语法：
Class obj;
obj.~Class();
将在该对象上调用析构函数。但是，您应该NOT执行此操作。例如：
#include <cstdio>
class Foo {
public:
Foo() {}
~Foo() {
printf("Destroya\n");
if (foo_m) delete foo_m;
}
private:
int* foo_m = new int(42);
};
int main() {
Foo foo;
foo.~Foo();
}
您可以从输出中看到，析构函数被调用两次。第一次，当我们手动“销毁”一个对象时，又是当它实际上离开堆栈时。
几乎永远不会手动调用析构函数。该对象不会消失，您只需打破其状态并获得未定义的行为。您真正想要的可能是clear()或reset()函数，用于重新初始化状态。或按照注释中的建议，您可以将分配默认对象移动到已经存在的对象中，以重置状态，而无需编写其他功能。
析构函数通常不是您手动调用的东西。对于堆栈上的内存，当对象超出范围时，将自动调用析构函数。对于堆上的内存，使用delete时将调用析构函数。在这种情况下，您实际上并不想删除它，而只想重置它。 deck = Deck()将“重置”它并为您提供默认的构造Deck对象。
[如何[开始]，我在游戏仍在进行且主游戏仍在运行时从新手和副牌开始
根本上，您只需要在一个位置调用play：在main的内循环之外（“当回合还没有结束时”）。除了所有重复的代码外，您的问题是，当玩家想再次玩游戏时，请将quit和quitGame都设置为false，这样内循环就不会终止，并且甲板也不会重新洗牌。
[其他问题，留给读者练习：response在分配值之前可以先阅读。您的shuffle例程不是很好，因为很多卡都不会移动。