设计模式 Design Parttern ——策略模式Strategy

设计模式 Design Parttern ——策略模式Strategy

http://blog.csdn.net/leeidea/

 

1:头文件

 

#ifndef _STRATEGY_H_VANEY_#define _STRATEGY_H_VANEY_#include <iostream>using namespace std;/******************************************************************名称 ：Strategy.h版本 ：1.00描述 ：演示策略模式的概念作者 ：[e-mail] http://blog.csdn.net/leeidea日期 ：2010年10月22日版权 ：[e-mail] http://blog.csdn.net/leeide******************************************************************//*官方解释：A Strategy defines a set of algorithms that can be used interchangeably.我的理解：提供一组算法组，该算法组的算法实现同一个目的，可以替换，注意与Bridge模式区别， 桥模式也是提供一个统一接口和一组不同的实现接口，统一接口具体调用哪个实现接口是 在程序运行中决定的。*///抽象解码算法class CDecode{public:CDecode(){cout << "CDecode()" << endl;}virtual ~CDecode(){cout << "~CCalculate()" << endl;}public://需要子类实现的方法virtual void DecodeH264() = 0;};//硬解码算法class CHardDecode : public CDecode{public:CHardDecode(){cout << "CHardDecode()" << endl;}virtual ~CHardDecode(){cout << "~CHardDecode()" << endl;}public:virtual void DecodeH264(){cout << "CHardDecode DecodeH264" << endl;}};//软解码算法class CSoftDecode : public CDecode{public:CSoftDecode(){cout << "CSoftDecode()" << endl;}virtual ~CSoftDecode(){cout << "~CSoftDecode()" << endl;}public:virtual void DecodeH264(){cout << "CSoftDecode DecodeH264" << endl;}};//H264解码使用过程class CProcessH264{CDecode* _decode;public:CProcessH264(CDecode* decode){_decode = decode;cout << "CProcessH264(Parameter)" << endl;}CProcessH264(){cout << "CProcessH264()" << endl;}virtual ~CProcessH264(){if(_decode)delete _decode;_decode = 0;cout << "~CProcessH264()" << endl;}public:void SetDecoder(CDecode* decode){_decode = decode;cout << "SetCalculate" << endl;}void Decode(){cout << "Decode" << endl;if(_decode)return _decode->DecodeH264();}};#define C_API extern "C"//用户C_API int UsingSG();#endif

2:源文件

 

#include "Strategy.h"C_API int UsingSG(){//创建解码算法CSoftDecode* decode1 = new CSoftDecode();CHardDecode* decode2 = new CHardDecode();//初始为软解码CProcessH264* process = new CProcessH264(decode1);process->Decode();//提高效率，改成硬解码process->SetDecoder(decode2);process->Decode();return 1;}

3:用户文件main.c

 

extern int UsingSG();//系统默认入口int _tmain(int argc, _TCHAR* argv[]){ return UsingSG();}