验证代码

#include<iostream>
using namespace std;
class bass1{
public:
  virtual void display()
  {
    cout<<"bass1"<<endl;
  }
};

class bass2:public bass1{
public:
  virtual void display()
  {
    cout<<"bass2"<<endl;
  }
};

class bass3:public bass1{
public:
  virtual void display()
  {
    cout<<"bass3"<<endl;
  }
};
void fun(bass1 *e)
{
  e->display();
}

int main()
{
bass1 a;
bass2 b;
bass3 c;
c.bass1::display();

fun(&a);
fun(&b);
fun(&c);
  return 0;
}

程序运行结果

C++--虚函数（验证）_C++