聚合類顯示默認構造函數

我正在爲我的C++類寫一個Ticket Simulator程序。我在名爲Parking Ticket的課程中有一個名爲PoliceOfficer的課程。當我在源中顯示officer.print()函數時，它顯示用戶提供的正確信息。但是，當我在ParkingTicket類中使用officer.print()函數時，它不顯示任何內容，即默認的構造函數。希望這是有道理的。這裏是我的代碼：聚合類顯示默認構造函數

class PoliceOfficer 
{ 
private: 
ParkedCar car; 
ParkingMeter time; 
std::string name; 
int badgeNumber; 

public: 
PoliceOfficer() 
{ 
    name = ""; 
    badgeNumber = 0; 
} 

PoliceOfficer(std::string i,int j) 
{ 
    name = i; 
    badgeNumber = j; 
} 
void set(std::string i, int j) 
{ 
    name = i; 
    badgeNumber = j; 
} 
std::string get_name() const 
{ 
    return name; 
} 
int get_badgeNum() const 
{ 
    return badgeNumber; 
} 

void print() const 
{ 
    std::cout << "Police Officer Information: " << std::endl; 
    std::cout << "Name: " << get_name() << std::endl; 
    std::cout << "Badge Number: " << get_badgeNum() << std::endl; 
} 
};

停車票類：

class ParkingTicket 
{ 
private: 
    ParkedCar car; 
    PoliceOfficer officer; 
    ParkingMeter time; 
    double fine; 
    int hours; 

public: 
    double baseFine = 25.0, hourlyFine = 10.0; 
    ParkingTicket(int i = 0, int j = 0) 
    { 
     fine = i; 
     hours = j; 
    } 
    void set_fine() 
    { 
     hours = (time.get_MinutesPurch() - car.get_minutesParked())/60; 
     fine += baseFine; 
     fine += hours *hourlyFine; 

    } 
    void ticket_print() const 
    { 
     officer.print(); 
    } 
    void print() 
    { 
     std::cout << "Ticket Information: " << std::endl; 
     std::cout << "Minutes in Violation: " << (car.get_minutesParked() -  time.get_MinutesPurch()) << std::endl; 
     std::cout << "Fine: $" << fine << std::endl; 

    }

};

源：

int main() 
{ 
    string oname; 
    int bnum; 
    PoliceOfficer officer; 
    ParkingTicket ticket; 
    cout << "Enter your name: "; 
    getline(cin, oname); 
    cout << "Enter your badge number: "; 
    cin >> bnum; 
    officer.set(oname, bnum); 
    officer.print(); 
    ticket.ticket_print(); 
    return 0; 
}

來源

2016-03-22 Thao

你在哪裏設置'ParkingTicket'裏面'PoliceOfficer'的信息？ –

我不？我一定要嗎？我認爲它只會從警察類 – Thao

@Thao'ParkingTicket'中設置信息，似乎需要對「PoliceOfficer」類實例進行初始化引用。 –

的PoliceOfficer對象在主（）是不一樣的你的ParkingTicket類內的PoliceOfficer。

ticket.officer.set(oname, bnum); 
ticket.officer.print(); 
ticket.ticket_print();

這工作，如果officer是不是私人的，所以你可能把它公開或創建一個返回引用或指向您的私人官成員函數：

ticket.officer().set(oname, bnum); 
ticket.officer().print(); 
ticket.ticket_print(); 

ticket.officer()->set(oname, bnum); 
ticket.officer()->print(); 
ticket.ticket_print();

這裏的另一種選擇：

ticket.set_officer_details(oname, bnum); 
ticket.print_officer_details(); 
ticket.ticket_print();

來源

2016-03-22 19:02:47 James

聚合類顯示默認構造函數

回答

相關問題