context.h

c++程序

//context.h
#ifndef _CONTEXT_H_ 
#define _CONTEXT_H_

class State; /** * **/ 

class Context 
{ 
public: 
	Context();
	Context(State* state);
	~Context();
	void OprationInterface();
	void OperationChangState();
protected:
private: 
	friend class State; //表明在State类中可以访问Context类的private字段
	bool ChangeState(State* state);
private: 
	State* _state;
};
#endif