深入解析C++编程中对设计模式中的策略模式的运用

#include <iostream> 
using namespace std; 
 
class WeaponBehavior 
{ 
public: 
  void virtual useWeapon() = 0; 
}; 
 
class AK47:public WeaponBehavior 
{ 
public: 
  void useWeapon() 
  { 
    cout << "Use AK47 to shoot!" << endl; 
  } 
}; 
 
class Knife:public WeaponBehavior 
{ 
public: 
  void useWeapon() 
  { 
    cout << "Use Knife to kill!" << endl; 
  } 
}; 
 
class Character 
{ 
public: 
  Character() 
  { 
    weapon = 0; 
  } 
  void setWeapon(WeaponBehavior *w) 
  { 
    this->weapon = w; 
  } 
  void virtual fight() = 0; 
protected: 
  WeaponBehavior *weapon; 
}; 
 
class King:public Character 
{ 
public: 
  void fight() 
  { 
    cout << "The king:" ; 
    if ( this->weapon == NULL) 
    { 
      cout << "You don't have a weapon! Please Set Weapon!" << endl; 
    } 
    else 
    {  
      weapon->useWeapon(); 
    } 
  } 
}; 
int main() 
{   
  WeaponBehavior *ak47 = new AK47(); 
  WeaponBehavior *knife = new Knife();    
 
  Character *kin = new King();    
 
  kin->fight();   
  cout << endl;  
 
  kin->setWeapon(ak47); 
  kin->fight(); 
  cout << endl; 
 
  kin->setWeapon(knife); 
  kin->fight(); 
 
  return 0; 
}