多态以及虚析构函数的使用

为什么要有虚析构函数？因为在实现多态时，当用基类操作派生类，在析构时防止只析构基类而不析构派生类的状况发生。

/*
  多态 
  虚析构函数 
  programmer:qpz
  time:2014-11-05
*/
#include <iostream>
const int MAX=3;
using namespace std;
class Base{
    private:
        int i;
        public:
    Base(void){
            //  this->i=i;
            }
      void  virtual sbsb(void)=0;
    virtual ~Base(){
                cout<<"~Base"<<endl;
            } 
};
class my:public Base{
    public:
      void sbsb(void){
        cout<<"mymymyymy"<<endl;
      }

      ~my(){
        cout<<"~my"<<endl;
      }

};
class you:public Base{
    public:
      void sbsb(void){
        cout<<"youyouyou"<<endl;
      }
      ~you(){
        cout<<"~you"<<endl;
      }

};
class her:public Base{
    public:
      void sbsb(void){
        cout<<"her"<<endl;
      }
      ~her(){
        cout<<"~her"<<endl;
      }

};
int main(void)
{
    Base *a[MAX]={new my(),new you(),new her()};
    for(int i=0;i<3;i++){
        a[i]->sbsb();
        delete a[i];
    }

    return 0;
} 

• 一个多态的实践

#include "stdafx.h"
#include <iostream>
using namespace std;
class CPerson
{
public:
    CPerson(int iAge, char* sName)
    {
        this->iAge = iAge;
        strcpy_s(this->sName,32,sName);//安全的拷贝函数
    }
    virtual char* WhoAmI()
    {
        return "I'm a person";
    }
private:
    int iAge;
    char sName[32];
};
class CWorker :public CPerson
{
public:
    CWorker(int iAge, char *sName, char *sEmploymentStatus) :CPerson(iAge, sName)
    {
        strcpy_s(this->sEmploymentStatus, 32, sEmploymentStatus);
    }
    virtual char* WhoAmI()
    {
        return "I'm a Worker";
    }
private:
    char sEmploymentStatus[32];
};
class CStudnet :public CPerson
{
public:
    CStudnet(int iAge, char *sName,char *sStudentIdentityCard):CPerson(iAge,sName)
    {
        strcpy_s(this->sStudentIdentityCard, 32, sStudentIdentityCard);
    }
    virtual char* WhoAmI()
    {
        return "I'm a Student";
    }
private:
    char sStudentIdentityCard[32];
};

/*
    面向对象之方法的重载
*/
int _tmain(int argc, TCHAR* argv[])
{
    CPerson cperson(10, "John");
    CWorker cworker(35,"Mary","On wacation");
    CStudnet cstudent(18, "pp", "Phisician");

    cout << cperson.WhoAmI() << endl;
    cout << cworker.WhoAmI() << endl;
    cout << cstudent.WhoAmI() << endl;
    cin.get();
    return 0;
}