帮忙解决一个简单问题

[asuccessa]

#include <iostream.h>

class Screen {
public:
//typedef Screen& (Screen::*Action) ();
typedef Screen& (*Action) ();
int Screen::*pi;
int i;
Action Menu[];
Screen() {
Menu[] = { &home, &forward, &back, &up, &down };
pi=&i;
}
Screen& home();
Screen& forward();
Screen& back();
Screen& down();
Screen& up();
public:
enum Directions { HOME, FORWARD, BACK, UP, DOWN };
Screen& move(Directions);
};



Screen& Screen::move(Directions cm)
{
// (this->*Menu[cm]) ();
Menu[cm] ();
return *this;
}

void main()
{
int Screen::*pm = &Screen::i;
Screen s;
}

想请大家帮忙看一下上面的代码哪出错了，然后想请教一下大家类成员指针是干什么用的，一般在什么时候用？

[waizqfor]

[Quote=引用楼主 asuccessa 的帖子:]
#include <iostream.h>

class Screen {
public:
//typedef Screen& (Screen::*Action) ();
typedef Screen& (*Action) ();
int Screen::*pi;
int i;
Action Menu[];
Screen() {
Menu[] = { &home, &forward, &back, &up, &down };
pi=&i;
}
Screen& home();
Screen& forward();
Screen& back();
Screen& down();
Screen& up();
public:
enum Directions { HOME, FORWARD, BACK, UP, DOWN …
[/Quote]
http://www.diybl.com/course/3_program/c++/cppsl/20071119/86994.html
LZ仔细看看指向类成员的指针吧 代码里错误很多 比如Menu[] = { &home, &forward, &back, &up, &down }; 这个赋值就错了
还有Action 的声明等等 先熟悉下语法吧

[feng4206yu]

#include <iostream>
using namespace std;

class Screen { 
public: 
	typedef Screen& (Screen::*Action) (); 
// 	typedef Screen& (*Action) (); 
// 	int Screen::*pi; 
// 	int i;
	Screen& home() {cout<<"home"<<endl; return *this;}; 
	Screen& forward() {cout<<"forward"<<endl; return *this;}; 
	Screen& back() {cout<<"back"<<endl; return *this;}; 
	Screen& down() {cout<<"down"<<endl; return *this;}; 
	Screen& up() {cout<<"up"<<endl; return *this;};
	
	static Action Menu[5]; 
	Screen()
	{ 
// 		Menu[0] = &home;
// 		Menu[1] = &forward;
// 		Menu[2] = &back; 
// 		Menu[3] = &up;
// 		Menu[4] = &down; 
// 		pi=&i; 
	} 
	
public: 
	enum Directions { HOME, FORWARD, BACK, UP, DOWN }; 
	Screen& move(Directions); 
}; 

Screen::Action Screen::Menu[] = {&Screen::home, &Screen::forward, &Screen::back, 
								&Screen::up, &Screen::down};


Screen& Screen::move(Directions cm) 
{ 
	 (this->*Menu[cm]) (); 
// 	Menu[cm] (); 
	return *this; 
} 

int main() 
{ 
// 	int Screen::*pm = &Screen::i; 
	Screen s;
	s.move(Screen::HOME);
	s.move(Screen::UP);
	return 0;
}