编译器错误：从 'const char*' 到 'char' 的无效转换

Question

由于 const char * 的错误，我在编译程序时遇到问题。这是我第一次使用它，我无法绕过它。即使这不是代码的问题，也有人可以链接或解释 const char *？谢谢！

我尝试将不同的 char 数据类型更改为 const char，但这不起作用。在发布此内容之前，我曾尝试在不同的领域进行查找，但我发现没有一个正在使用方法。

代码如下：

#include <iostream>
#include <iomanip>
#include <cstdlib>
#include <cstring>

using namespace std;


class Card
{
    public:
        Card();
        Card(int, char);
        
        void setCard(int, const char);
        
        int getFace();
        
        const char getSuit();
        
        void displayCard();
        
    private:
        int faceValue;
        char suitValue[9];
        
};


int main()
{
    //Set the seed value for the random number generator
srand(11);

//Test 1: Constructors and displayCard method

//Create the 3 Card objects

Card firstCard;
Card secondCard;
Card thirdCard = Card( 13, "Spades" );

//Display the 3 objects

cout << "Test 1: Constructors and displayCard method" << endl << endl
     << "  The first card is the ";
firstCard.displayCard();

cout << "." << endl << endl << "  The second card is the ";
secondCard.displayCard();

cout << "." << endl << endl << "  The third card is the ";
thirdCard.displayCard();


//Test 2: setCard method on the first object

cout << endl << endl << endl << "Test 2: setCard method" << endl << endl;

//Change the first card to the Jack of Hearts

firstCard.setCard( 11, "Hearts" );

cout << "  Change the first card to the Jack of Hearts. It is now the ";
firstCard.displayCard();


//Test 3: setCard method on the second object

cout << endl << endl << endl << "Test 3: setCard method with invalid values" << endl << endl;

//Try to change the second card using face of -5 and suit of ""

secondCard.setCard( -5, "" );

cout << "  The second card should be the Ace of Hearts. It is now the ";
secondCard.displayCard();

//Try to change the first card using face of 16 and suit of "Candles"

firstCard.setCard( 16, "Candles" );

cout << endl << endl << "  The first card should be the Ace of Hearts. It is now the ";
firstCard.displayCard();



//Test 4: getFace and getSuit methods on the third object

//Change the third card to 3 of Clubs
thirdCard.setCard( 3, "Clubs" );

cout << endl << endl << endl << "Test 4: getFace and getSuit methods" << endl << endl;

cout << "  The third card should have a face value of 3. It is "
     << thirdCard.getFace() << endl
     << "  The suit value should be Clubs. It is " << thirdCard.getSuit() << endl;

    
    return 0;
}


Card::Card()
{
    faceValue = (rand() % 13) + 1;
    
    int stringValue = (rand() % 4) + 1;
    
    switch(stringValue)
    {
        case 1: 
                strcpy(suitValue, "Clubs");
                break;
                
        case 2:
                strcpy(suitValue, "Diamonds");
                break;
                
        case 3:
                strcpy(suitValue, "Hearts");
                break;
                
        case 4:
                strcpy(suitValue, "Spades");
                break;
                
        default:
                cout << "Your string random number generator is broken";
    }
}


Card::Card(int face, char suit)
{
    setCard(int newFace, const char newSuit[]);
}


void setCard(int newFace, const char newSuit[])
{
    int hearts, diamonds, spades, clubs;
    
    if(newFace > 0 and newFace < 14)
    {
        faceValue = newFace;
    }
    else
    {
        faceValue = 1;
    }
    
    hearts = strcmp(suitValue, newSuit);
    diamonds = strcmp(suitValue, newSuit);
    spades = strcmp(suitValue, newSuit);
    clubs = strcmp(suitValue, newSuit);
    
    if(hearts == 0 or diamonds == 0 or spades == 0 or clubs == 0)
    {
        strcpy(suitValue, newSuit);
    }
    else
    {
        strncpy(suitValue, newSuit["Hearts"], 9);
    }
    
}


int Card::getFace()
{
    return faceValue;
}


const char * Card::getSuit()
{
    return suitValue;
}


void displayCard()
{
    switch(faceValue)
    {
        case 1: 
                cout << "Ace of " << suitValue << endl;
                break;
                
        case 11:
                cout << "Jack of " << suitValue << endl;
                break;
                
        case 12:
                cout << "Queen of " << suitValue << endl;
                break;
                
        case 13:
                cout << "King of " << suitValue << endl;
                break;
                
        default:
                cout << faceValue << " of " << suitValue << endl;
    }
}

Answer 1

在您的构造函数中，您的面值参数是char 类型（一个字符）。但是，当您调用所述构造函数时，您会给出一个字符串（在 c 中，字符串是一个字符数组，因此是 char *）。因为您使用的是 C++，所以我建议您使用字符串数据类型。