设计模式实例-简单工厂模式-优快云博客

本文链接：https://blog.youkuaiyun.com/tsgx_1989/article/details/44832513

本文详细介绍了使用简单工厂模式在C#中创建不同数学运算类的实例，包括加、减、乘、除四种基本运算，并通过客户端代码演示如何使用工厂模式进行操作数的输入和结果的获取。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

using System;

namespace Ahoo.Demo.DesignPatterns.Patterns.SimpleFactory
{
    /// <summary>
    /// 简单工厂类
    /// </summary>
    public class OperationFactory
    {
        public static Operation CreateOperation(string oper, double FirstNumber = 0, double SecondNumber = 0)
        {
            Operation _Operation;
            switch (oper)
            {
                case "+":
                    _Operation = new AddOperation
                    {
                        FirstNumber = FirstNumber,
                        SecondNumber = SecondNumber
                    };
                    break;
                case "-":
                    _Operation = new SubOperation
                    {
                        FirstNumber = FirstNumber,
                        SecondNumber = SecondNumber
                    };
                    break;
                case "*":
                    _Operation = new MulOperation
                    {
                        FirstNumber = FirstNumber,
                        SecondNumber = SecondNumber
                    };
                    break;
                case "/":
                    _Operation = new DivOperation
                    {
                        FirstNumber = FirstNumber,
                        SecondNumber = SecondNumber
                    };
                    break;
                default:
                    throw new ArgumentException("操作符有误！");
            }
            return _Operation;
        }
    }
    /// <summary>
    /// 抽象类
    /// </summary>
    public abstract class Operation
    {
        public double FirstNumber { get; set; }
        public double SecondNumber { get; set; }
        public abstract double GetResult();
    }
    /// <summary>
    /// 具体操作子类(+)
    /// </summary>
    public class AddOperation : Operation
    {
        public override double GetResult()
        {
            double result = FirstNumber + SecondNumber;
            return result;
        }
    }
    /// <summary>
    /// 具体操作子类(-)
    /// </summary>
    public class SubOperation : Operation
    {
        public override double GetResult()
        {
            double result = FirstNumber - SecondNumber;
            return result;
        }
    }
    /// <summary>
    /// 具体操作子类(*)
    /// </summary>
    public class MulOperation : Operation
    {
        public override double GetResult()
        {
            double result = FirstNumber * SecondNumber;
            return result;
        }
    }
    /// <summary>
    /// 具体操作子类(/)
    /// </summary>
    public class DivOperation : Operation
    {
        public override double GetResult()
        {
            if (SecondNumber == 0)
            {
                throw new ArgumentException("参数[SecondNumber]不能为0！");
            }
            double result = FirstNumber / SecondNumber;
            return result;
        }
    }


    public class Client
    {
        public static void Execute()
        {
            Console.WriteLine("********请输入操作符********");
            string str_oper = Console.ReadLine();
            Operation operation = OperationFactory.CreateOperation(str_oper);
            Console.WriteLine("请输入操作符 第一个操作数");
            operation.FirstNumber = Double.Parse(Console.ReadLine());
            Console.WriteLine("请输入操作符 第二个操作数");
            operation.SecondNumber = Double.Parse(Console.ReadLine());
            Console.WriteLine("结果为：{0}", operation.GetResult());
        }
    }
}