大话设计模式简单工厂模式c++实现

简单工厂模式

大部分都是大话设计模式上的案例，工厂方法对着简单工厂写的，和书上案例不一致

#include<iostream>

using namespace std;
//简单工厂模式
//抽象类
class AbstractOperation {
    
    
public:
	virtual int GetResult() = 0;
	void Get(int _NumberA,int _NumberB){
    
    
		this->NumberA = _NumberA;
		this->NumberB = _NumberB;
	}
protected:
	int NumberA = 0;
	int NumberB = 0;
};

//具体实现类
class OperationAdd : public AbstractOperation {
    
    
public:
	virtual int GetResult() {
    
    
		return NumberA + NumberB;
	}
};

class OperationSub : public AbstractOperation {
    
    
public:
	virtual int GetResult() {
    
    
		return NumberA - NumberB;
	}
};

class OperationMul : public AbstractOperation {
    
    
public:
	virtual int GetResult() {
    
    
		return NumberA * NumberB;
	}
};

class OperationDiv : public AbstractOperation {
    
    
public:
	virtual int GetResult() {
    
    
		return NumberA / NumberB;
	}
};

//工厂类-->扩展时需要修改源代码！！
class OperationFactory {
    
    
public:
	static AbstractOperation* Operated(char _str) {
    
       // (string str)
		switch (_str)   //(_str[0])
		{
    
    
		case '+':
			return new OperationAdd;
		case '-':
			return new OperationSub;
		case '*': 
			return new OperationMul;
		case '/':
			return new OperationDiv;
		default:
			break;
		}
	}
};

void test1() {
    
    
	OperationFactory* factory = new OperationFactory;
	AbstractOperation* operate = factory->Operated('*');   //string-->("*")
	operate->Get(5, 6);
	cout << operate->GetResult() << endl;

	delete operate;
	delete factory;
}
int main(void)
{
    
    
	test1();
	return 0;
}