7_66.cpp

几个C++程序设计实例

#include <iostream.h>
class cB
{
	public:
		cB();
		cB(int);
		~cB();
		int get(){return B_value;}
	protected:
		int B_value;
};
class cA
{
public:
	cA(int,int);
	~cA();
	int getcA(){ return b.get();}
protected:
	int a;
	cB b;
};
cB::cB()
{	B_value=1;
	cout<<"construct cB. B_value="<<B_value<<endl;
}
cB::cB(int v)
{
	B_value=v;
	cout<<"construct cB. B_value="<<B_value<<endl;
}
cB::~cB()
{	cout<<"destruct cB. B_value="<< B_value<<endl;
}

cA::cA(int v1,int v2)
{	a=v1;
	cB b(v2);              //调用cB的有参构造函数
	cout<<"construct cA. a="<<a<<endl;
}
cA::~cA()
{	cout<<"destruct cA."<<endl;
}
void main()
{	cA a(5,10);
    cout<<a.getcA()<<endl;
}