C++中Contestants类readFile单参数写入Player对象数组问题

我在实现Contestants类的readFile成员函数时遇到了问题——这个函数需要从文件读取内容，逐行解析成Player对象后追加到当前实例的数组里。之前我是通过把testList2对象以引用形式传入函数来实现的，但现在要求主文件不能修改，且readFile只能接收一个文件名参数。

测试代码片段 #

Contestants testList2;

std::cout << "-----BEGIN FILE I/O TEST -----------\n\n";
std::cout << "Test 1 - error opening file\n";
std::cout << "\tEXPECTING: Could not open file.\n";
std::cout << "\tACTUAL: ";
testList2.readFile("testFil");

std::cout << "\nTest 2 - append to object from file\n";
testList2.readFile("testFile2"); // 此处不能添加第二个参数

std::cout << "\nPrinting testList2 contents\n";
for(int i = 0; i < testList2.getSize(); i++) {
    std::cout << "Player " << i + 1 << "\n";
    std::cout << testList2.at(i) << std::endl;
}

readFile成员函数实现 #

bool Contestants::readFile(std::string fileName) {
    // Create object and open file
    Player tmpPlayer;
    std::ifstream inFile(fileName);

    // Check that file is open.
    if(!inFile) {
        std::cout << "Could not open file." << std::endl;
        return false;
    }
    std::cout << "File opened.\n" << std::endl;

    // Read the file line by line
    std::string line;
    std::string tmpName;
    std::string tmpScore;
    while(std::getline(inFile, line)) {
        //std::cout << line << std::endl; // This line is for testing purposes
        
        // Create a string stream read from input file.
        std::stringstream ss(line);
        // Store contents of the file into two seperate value delimited by a comma.
        if(std::getline(ss, tmpName, ',')) {
            if(std::getline(ss, tmpScore)) {
                tmpPlayer = Player(tmpName, stoi(tmpScore));
                testList2.append(tmpPlayer); // 如何在无需第二个参数的情况下追加到当前Contestants对象？
            }
        }
    }
    
    // Check for errors or end of file
    if (inFile.bad()) {
        std::cout << "Error reading file." << std::endl;
        return false;
    } else if (inFile.eof()) {
        std::cout << "\nEnd of file reached." << std::endl;
    }
    
    // Close the file.
    inFile.close();
    std::cout << "\nFile closed." << std::endl;
    return true;
}

Contestants类定义 #

class Contestants
{

    public:
        // Static constant size maximum for array size.
        static const int MAX_SIZE = 3;

        // Default constructor
        Contestants();
    
    
        // Capacity
        int getSize()    const;  // Returns the number of objects held within Contestants
        int getMaxSize() const;  // Returns the value of MAX_SIZE
        bool isEmpty()   const; // Checks for empty object array.
        
        // Accessors
        int contains(const Player& player) const;  // Determines if Contestants contains specified Player object
        const Player& at(int index) const;        // Returns player object found at index param
        const Player& operator[](int index) const; // TODO
        
        // Modifiers
        void clearAll();                       // Resets object array to 0.
        bool append(const Player& player);      // Adds player objects and increases size.
        bool removePlayer(const Player& player); // Finds player object and calls removeByIndex()
        bool removeByIndex(int index);          // removes specified player object

        // Other (file IO)
        bool readFile(std::string fileName);  // TODO
        bool writeFile(std::string fileName); // TODO
    
    
    
    private:
        Player data[MAX_SIZE];
        int size;


};

我试过多种指针方法但都报错，希望得到方向指引而非直接答案。

内容的提问来源于stack exchange，提问作者MadTragic