《C／C++程序员实用大全》配套代码,适用初学C++的人员。

				#include 
				
				class base 
				{
				 public:
				   virtual void vfunc(void)
				    {
				      cout 				    }
				 };
				
				class derived1 : public base 
				{
				 public:
				   void vfunc(void)
				    {
				      cout 				    }
				 };
				
				class derived2 : public derived1 
				{
				 public:
				   void vfunc(void)
				    {
				      cout 				    }
				 };
				
				void main(void)
				 {
				   base *p, b;
				   derived1 d1;
				   derived2 d2;
				
				   p = &b;        // Point to base class
				   p->vfunc();
				   p = &d1;       // Point to first derived class
				   p->vfunc();
				   p = &d2;       // Point to second derived class
				   p->vfunc();
				 }