大话设计模式之C++实现---简单工厂模式

呵呵，这段时间为了找工作，很多东西都没去学了！还是跟以前一样学完一样，再学另一样。每天进一小步，都有新的高度！

本程序是从大话设计模式里面所提出的，我用C++来实现（我总是没事就把C#改为C++,看来有时间也去学下。net的）

下面是 factory.h

#include <exception>#include <string>#include <iostream>using namespace std;#ifndef AFX_CLASS_OPERATION#define AFX_CLASS_OPERATIONtemplate <class T>class Operation{public:virtual T GetResult(){T result = 0;return result;}virtual Operation& operator =(const Operation &A){return *this;}public:T _numberA;T _numberB;};//加法template <class T>class OperationAdd:public Operation<T>{public:virtual T GetResult(){T result = 0;result = _numberA + _numberB;return result;}};//减法template <class T>class OperationSub:public Operation<T>{public:virtual T GetResult(){T result = 0;result = _numberA - _numberB;return result;}};//乘法template <class T>class OperationMul:public Operation<T>{public:virtual T GetResult(){int result = 0;result = _numberA * _numberB;return result;}};//除法template <class T>class OperationDiv:public Operation<T>{public:virtual T GetResult(){T result = 0;if(_numberB == 0){throw 1001;}result = _numberA / _numberB;return result;}};#endif//类工厂#ifndef AFX_CLASS_OPERATIONFACTORY#define AFX_CLASS_OPERATIONFACTORYtemplate <class T>class OperationFactory{public:static Operation<T>* CreateOperate(string operate){Operation<T> *oper=NULL;if(!operate.compare("+"))oper = new OperationAdd<T>;if(!operate.compare("-"))oper = new OperationSub<T>;if(!operate.compare("*"))oper = new OperationMul<T>;if(!operate.compare("/"))oper = new OperationDiv<T>;return oper;}};#endif

 

接着是主程序：

#include "factory.h"#include <conio.h>int main(int argc,char *argv[]){Operation<int> *oper = NULL;oper = OperationFactory<int>::CreateOperate("+");oper->_numberA = 1;oper->_numberB = 2;cout<<oper->GetResult()<<endl;getch();return 1;}