设计模式-策略模式

应用场景：
将一系列算法封装起来，当算法发生变化时，通过更改算法接口实现更换算法；

代码实现：

#include<iostream>
using namespace std;

class Operator
{
public:
	double dLeftOperator;
	double dRightOperator;
	virtual double GetResult() = 0;
	virtual void SetValue(double leftValuue, double rightValue) = 0;
};

class OperatorA :public Operator
{
public:
	void SetValue(double leftValuue, double rightValue)
	{
		this->dLeftOperator = leftValuue;
		this->dRightOperator = rightValue;
	}
	double GetResult()
	{
		return dLeftOperator + dRightOperator;
	}
};

class context
{
private:

	Operator* op;
public:
	context(Operator* op)
	{
		this->op = op;
	}
	void DisplayResult()
	{
		cout << op->GetResult() << endl;
	}
};


int main()
{
	Operator* op = nullptr;
	op = new OperatorA;
	op->SetValue(12.1, 22.3);
	context* ct = new context(op);
	ct->DisplayResult();

	delete ct;
	delete op;

	return system("pause");
}