源程序：
#include<iostream>
using namespace std;
class CBase
{
protected:
int n;
public:
CBase(int i) :n(i) {}
void Print()
{
cout << "CBase:n=" << n << endl;
}
};
class CDerived :public CBase
{
public:
int v;
CDerived(int i) :CBase(i), v(2 * i) {}
void Func() {};
void Print()
{
cout << "CDerived:n=" << n << endl;
cout << "CDerived:v=" << v << endl;
}
};
int main()
{
CDerived objDerived(3);
CBase objBase(5);
CBase *pBase = &objDerived;
CDerived *pDerived;
pDerived = &objDerived;
cout << "使用派生类指针调用函数" << endl;
pDerived->Print();
pBase = pDerived;
cout << "使用基类指针调用函数" << endl;
pBase->Print();
//pBase->Func(); //错误，通过基类指针不能调用派生类函数
//pDerived=pBase; //错误，派生类指针=基类指针
pDerived = (CDerived*)pBase; //强制类型转换，派生类指针=基类指针
cout << "使用派生类指针调用函数" << endl;
pDerived->Print();
system("pause");
return 0;
}
运行结果：
