简单工厂模式的四则运算设计

最新推荐文章于 2021-12-04 11:04:30 发布

原创最新推荐文章于 2021-12-04 11:04:30 发布 · 1.5k 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#class #string #exception #测试

Design pattern 专栏收录该内容

5 篇文章

订阅专栏

本文介绍了一种基于工厂模式和继承的计算器实现方法，通过定义一个运算基类Operation及四个子类来完成加减乘除操作，并使用OperationFactory工厂类根据不同运算符创建对应的子类实例。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

具体代码：

using System;

// 二元运算的基类
public class Operation
{
    //私有成员
    private double _numberA = 0;
	private double _numberB = 0;
	
	//公共属性
	public double NumberA
	{
	    get { return _numberA;}
		set { _numberA = value;}
	}
	public double NumberB
	{
	    get { return _numberB; }
		set { _numberB = value; }
	}
	
	//虚函数
	public virtual double GetResult()
	{
	    double result = 0;
		return result;
	}
}

// 四则运算类
class OperationAdd : Operation
{
    //重写基类的虚函数
    public override double GetResult()
	{
	    double result = 0;
		result = NumberA + NumberB;
		return result;
	}
	
}

class OperationSub : Operation
{
    public override double GetResult()
	{
	    double result = 0;
		result = NumberA - NumberB;
		return result;
	}
}

class OperationMul : Operation
{
    public override double GetResult()
	{
	    double result = 0;
		result = NumberA * NumberB;
		return result;
	}
}

class OperationDiv : Operation 
{
    public override double GetResult()
	{
	    double result = 0;
		if(NumberB != 0)
		{
		    result = NumberA / NumberB;
		}
		else
		{
		    throw new Exception("can't divided by 0");
		}
		return result;
	}
}

// 工厂类
public class  OperationFactory
{
    public static Operation CreateOperation(string operate)
	{
	    Operation oper = null;
		switch (operate)
		{
			case "+":
				oper = new OperationAdd();
				break;
			case "-":
			    oper = new OperationSub();
				break;
			case "*":
			    oper = new OperationMul();
				break;
			case "/":
			    oper = new OperationDiv();
				break;
		}
		return oper;
	}
}

//测试类

public class Test
{
    public static void Main(string[] args)
	{
	    //运算基类
	    Operation oper;
		Console.WriteLine("请输入运算符");
		// 运算符
		string strOperation = Console.ReadLine();
		// 利用工厂类生成运算类
		oper = OperationFactory.CreateOperation(strOperation);
		//输入数A、B
		Console.WriteLine("输入数A");
		oper.NumberA = Convert.ToDouble(Console.ReadLine());
		Console.WriteLine("输入数B");
		oper.NumberB = Convert.ToDouble(Console.ReadLine());
		//获得结果并输出
		double result = oper.GetResult();
		Console.WriteLine("结果是：" + result);
	}
}