无法从基类类型的指针访问派生类方法

I should specify that I'm a bit new to OOP. I'm tying to make a vector of type pointer to Person that has a method GetName() and access a method GetSpg() from my Player class that derives Person. I get an error "GetSpg() is not a member of Person". My question would be: is there any way to access both functions from the vector so that if it points to a Person to not show that method but if it is to do so?

这是我的代码:

#ifndef _PERSON_H
#define _PERSON_H

#include <iostream>
#include <algorithm>

typedef std::pair<std::string, std::string> StrPair;

class Person :private StrPair
{

  public:
    Person(const std::string& fn = "none", const std::string& sn = "none")         :StrPair(fn,sn){};
    virtual void Update(const std::string& fn, const std::string& sn){ StrPair::first = fn; StrPair::second = sn; };
    virtual const StrPair& GetName(){ return (const StrPair&)(*this); };
};
#endif

typedef std::pair<int, int> IntPair;

class Jucator: public Person, private IntPair
{
    std::string tip;
    int spg;
    int average;

  public:
    Jucator(const std::string& fn = "none", const std::string& sn = "none", 
        const std::string& t = "", const int& _spg = 0, const int& _avr = 0, 
        const int& _g = 0, const int& _r = 0) :Person(fn, sn),tip(t),spg(_spg),average(_avr),IntPair(_g,_r){};
    virtual void Update(const std::string& fn, const std::string& sn, const std::string& t, const int& _spg, const int& _avr,
        const int& _g, const int& _r){
    Person::Update(fn, sn); tip = t; spg = _spg; average = _avr; IntPair::first = _g; IntPair::second = _r;
};

virtual const int& GetSpg(){ return spg; };

推荐答案

你不能.Person 类型的指针只能用于访问属于 Person 对象的数据/地址(函数).编译器根本无法知道从 Person 派生的所有类可能是什么，因此哪些操作是合法的.

Player* pPlayer = dynamic_cast<Player*>(pPerson);
if (pPlayer) {
  //Use the pointer like a player pointer
  //Note: You can only call player functions from pPlayer, not pPerson
} else {
  //Use the pointer like a person pointer
}