求索阁

#include <iostream>
#include <list>
using namespace std;

//
struct IObserver
{
public:
    virtual ~IObserver() { }

    virtual void Update() = 0;
};

class CObserver : public IObserver
{
public:
    CObserver(string name) : m_name(name) { }
    virtual ~CObserver() { }

    virtual void Update() { cout<<m_name.c_str()<<" observer update."<<endl; }
   
private:
    string m_name;
};

class CBlog
{
public:
    void AddObserver(IObserver *pObserver) { m_pObserverList.push_back(pObserver); }
    void RemoveObserver(IObserver *pObserver) { m_pObserverList.remove(pObserver); }

    void Notify()
    {
        list<IObserver*>::iterator ite = m_pObserverList.begin();
        for(; m_pObserverList.end() != ite; ite++)
        {
            (*ite)->Update();
        }
    }
private:
    list<IObserver*> m_pObserverList;
};

//
void main()
{
    CBlog blog;
   
    CObserver observerA("AAA");
    CObserver observerB("BBB");

    blog.AddObserver(&observerA);
    blog.AddObserver(&observerB);

    blog.Notify();
}