c++ 命令模式（command）

命令模式的有点：

1.能够容易地设计一个命令队列；

2.在需要的情况下，可以比较容易地将命令记入日志。

3.可以容易的实现对请求的撤销和重做。

4.由于加进新的具体命令类不影响其他的类，因此增加新的具体命令类很容易。

#include <iostream>
#include <vector>

using namespace std;

class Reciever
{
public:
void Action()
{
cout << "Do action !!" <<endl;
}
};

class Icommand
{
public:
virtual ~Icommand() {}
virtual void Excute() = 0;
protected:
Icommand() {}
};

class Read_Command:public Icommand
{
public:
Read_Command(Reciever *rev):m_rev(rev)
{

}
virtual void Excute()
{
cout << "Read Command.." << endl;
m_rev->Action();
}
~Read_Command()
{

}
private:
Reciever *m_rev;
};

class Write_Command:public Icommand
{
public:
Write_Command(Reciever *rev):m_rev(rev)
{

}
virtual void Excute()
{
cout << "Read Command.." << endl;
m_rev->Action();
}
~Write_Command()
{

}
private:
Reciever *m_rev;
};

class Invoker
{
public:
Invoker(Icommand* cmd):m_cmd(cmd)
{

}
Invoker()
{

}
~Invoker()
{
delete m_cmd;
}
void Notify()
{
std::vector<Icommand*>::iterator it = cmdList.begin();
for(it;it != cmdList.end();++it)
{
m_cmd = *it;
m_cmd->Excute();
}
}
void AddCmd(Icommand* pcmd)
{
cmdList.push_back(pcmd);
}
void DelCmd(Icommand* pcmd)
{
//cmdList.pop_back();
}

private:
Icommand* m_cmd;
std::vector<Icommand*> cmdList;
};

主函数：

#include <iostream>
#include <vector>
#include "command.h"

using namespace std;

int main()
{
Reciever* rev = new Reciever();
Icommand* cmd1 = new Read_Command(rev);
Icommand* cmd2 = new Write_Command(rev);
Invoker inv;

inv.AddCmd(cmd1);
inv.AddCmd(cmd2);
inv.Notify();

system("pause");
return 0;
}