《C++》继承

继承

class A:public B

子类 : 继承方式 父类

class Phone
{
public:
	Phone()
	{
		frame = "框架";
		screen = "屏幕";
		battery = "电池";
	}
public:
	string frame;
	string screen;
	string battery;

};
class Brand:public Phone
{
public:
	Brand(string str)
	{
		brd = str;
	}
public:
	string brd;
};
ostream& operator<<(ostream &cout, Brand &p)
{
	cout << p.frame << endl;
	cout << p.screen<< endl;
	cout << p.battery << endl<<endl;
	cout << p.brd ;
	return cout;
}
void test()
{
	Brand  b1("水果");
	Brand  b2("为华");
	Brand  b3("大米");
	cout << b1<< endl;
	cout << "------------------------------" << endl;
	cout << b2<< endl;
	cout << "------------------------------" << endl;
	cout << b3 << endl;
}
int main()
{
	test();
	system("pause");
	return 0;
}

继承可以减少代码重复量

继承的同名成员访问

要使用.加作用域访问

class A
{
public:
	A()
	{
		m_a = 100;
	}
	int m_a;
};
class B : public A
{
public:
	B()
	{
		m_a = 200;
	}
	int m_a;
};
int main()
{
  B b;
	cout << "B.m_a= "<<b.m_a << endl;
	cout << "A.m_a= " << b.A::m_a << endl;
  system("pause");
  return 0;
}

多继承

一个儿子认多个爹

class A;
class B;
class C : public A, public B;

由于多继承使用较少只做了解