c++ - 仅使用 getName 在主函数中设置字符串名称

Question

我正在使用展示多态性的子类进行作业。该程序需要为每个新对象指定一个名称。我只应该有 string getName(){return name;} (这位于基类中)。每个类 class(string){} 中还有一个构造函数。在主函数中，我想为每个对象设置名称。非常感谢我应该如何做的任何建议!

h 文件:

#ifndef DUCK_H
#define DUCK_H
#include <string>
using namespace std;

class Duck
{
private:
    string name;
public:
    Duck(){}
    Duck(string){}
    string getName() { return name; };
    virtual string quack() {return "Which"; }
    virtual string fly() { return "How?"; }
};
class RubberDuck : public Duck
{
public:
    RubberDuck(){}
    RubberDuck(string) {}
    string quack() { return "Squeak"; }
    string fly() { return "Fly with bounce"; }
};
class MallardDuck : public Duck
{
public:
    MallardDuck(){}
    MallardDuck(string) {}
    string quack() { return "Quack"; }
    string fly() { return "Fly with wings"; }
};
class RocketDuck : public Duck
{
public:
    RocketDuck(){}
    RocketDuck(string) {}
    string quack() { return "Zoom"; }
    string fly() { return "Fly with rockets"; }
};
#endif // !1

cpp文件:

#include <iostream>
#include "Duck.h"
using namespace std;

//void display(Duck *d);

int main()
{
    Duck d1;
    MallardDuck md;
    RubberDuck rbd;
    RocketDuck rd;

    //for main duck
    //Duck duck("Donald");
    //cout << duck.getName();
    cout << d1.quack() <<"\n";
    cout << d1.fly() <<"\n";
    cout << "\n";
    //for rubber duck
    RubberDuck rbdname("Rubby");
    cout << rbd.quack() << "\n";
    cout << rbd.fly() << "\n";
    cout << "\n";
    //for mallard duck
    MallardDuck mdname("Mally");
    cout << md.quack() << "\n";
    cout << md.fly() << "\n";
    cout << "\n";
    // for rocket duck
    RocketDuck rdname("Rocky");
    cout << rd.quack() << "\n";
    cout << rd.fly() << "\n";
    cout << "\n";
    //polymorphism
    Duck *d2 = new MallardDuck();
    cout << d2->getName() << "\n";
    cout << d2->quack() << "\n";
    cout << d2->fly() << "\n";
    cout << "\n";

    return 0;
 }
/*void display(Duck d)
{
    cout << d.quack();
}
*/

Answer 1

您是在问如何调用您定义的构造函数吗？你会那样做

Duck duck("Drake Mallard");