constructor.cpp

来自「这个是我们学校用的VC++教案」· C++ 代码 · 共 36 行

#include  <iostream.h>
class  Point						// 定义基类Point
{
protected:
	int  x, y;
public:
	Point(int  a=0, int  b=0)		// 含有缺省参数值的构造函数也是默认的构造函数
	{ x=a; y=b; cout<<"Point constructor:"<<'['<<x<<','<<y<<']'<<endl; };
	~Point()
	{ cout<<"Point destructor:"<<'['<<x<<','<<y<<']'<<endl; };
};
class  Circle : public  Point		// 定义类Point的派生类
{
protected:
	int  radius;
public:
	Circle(int  a=0, int  b=0, int  r=0) : Point(a, b)		// 显式调用基类的构造函数
	{ radius=r;	cout<<"Circle constructor:"<<'['<<radius<<']'<<'['<<x<<','<<y<<']'<<endl; };
	~Circle()
	{ cout<<"Circle destructor:"<<'['<<radius<<']'<<'['<<x<<','<<y<<']'<<endl; };
};
class  Cylinder : public  Circle	// 定义类Circle的派生类	
{
protected:
	int  height;
public:
	Cylinder(int  a=0, int  b=0, int  r=0, int  h=0) : Circle(a, b, r)		// 显式调用基类的构造函数
	{ height=h;	cout<<"Cylinder constructor:"<<'['<<height<<']'<<'['<<radius<<']'
					<<'['<<x<<','<<y<<']'<<endl; };
	~Cylinder()
	{ cout<<"Cylinder destructor:"<<'['<<height<<']'<<'['<<radius<<']'<<'['<<x<<','<<y<<']'<<endl; };
};
main()
{
	Cylinder  cylinder(200, 300, 100, 400);		// 调用了类Point、Circle和Cylinder的构造函数
}