c++ - 创建自定义“字符串”(结构)拷贝

Question

我正在尝试创建一个函数来复制我的卡片结构。我只需复制 cvalue 即可轻松开始。然而，我的 cvalue 没有复制，当应该读取 1000 时它仍然读取 5。

#include <iostream>
#include <fstream>
#include <ctime>
#include <stdlib.h>
#include <string>

using namespace std;

//Structs
struct card 
{
    char suit[8];
    char rank[6];
    int cvalue;
    char location;
};

void copyCard(card destination, card source);

int main()
{
    card card1;
    card card2;
    card1.cvalue = 1000;

    card2.cvalue = 5;
    card *card1p = &card1;

    copyCard(card2, card1);
    cout << card2.cvalue << endl;

}

void copyCard(card destination, card source)
{
    card *myPointer;
    myPointer = &source;
    (*myPointer).cvalue = source.cvalue;
    myPointer = &destination;
    destination.cvalue = (*myPointer).cvalue;
}

Answer 1

如果您打算将 source 复制到目标，那么您可以将 source 设为 const & (没有必要修改它)并且目标是引用或指针。

void copyCard(card& destination, const card& source)
{
  destination = source;
}

int main()
{
  card card1, card2;

  card1.cvalue = 1000;
  card2.cvalue = 5;

  copyCard(card2, card1);
  cout << card2.cvalue << endl;
}

但是，您的 copyCard 功能根本没有理由。您可以通过简单的赋值将card1复制到card2。

card2 = card1;