。net简单工厂模式

来源：互联网发布：qt编程快速入门 pdf 编辑：程序博客网时间：2024/06/06 00:44

在我理解中，工厂模式就是用来方便添加的，主要是运用了接口和虚函数的方法，来达到实现的目的，灵活性强。

using System;

using System.Collections.Generic;
using System.Text;

namespace OOPTest
{
    // 运算接口
    interface IOperation
    {
        double GetResult(double numberA, double numberB);
    }

    //加法类
    class OperationAdd : IOperation
    {
        public double GetResult(double numberA, double numberB)
        {
            double result = 0;
            result = numberA + numberB;
            return result;
        }
    }

    //减法类
    class OperationSub : IOperation
    {
        public double GetResult(double numberA, double numberB)
        {
            double result = 0;
            result = numberA - numberB;
            return result;
        }
    }

    //乘法类
    class OperationMul : IOperation
    {
        public double GetResult(double numberA, double numberB)
        {
            double result = 0;
            result = numberA * numberB;
            return result;
        }
    }

    //除法类
    class OperationDiv : IOperation
    {

        public double GetResult(double numberA, double numberB)
        {

            double result = 0;
            if (numberB == 0)
                throw new Exception("除数不能为0。");
            result = numberA / numberB;
            return result;
        }
    }

    //运算类工厂
    class OperationFactory
    {
        public static IOperation createOperate(string operate)
        {
            IOperation 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;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                Console.Write("请输入数字A：");
                string strNumberA = Console.ReadLine();

                Console.Write("请选择运算符号(+、-、*、/)：");
                string strOperate = Console.ReadLine();

                Console.Write("请输入数字B：");
                string strNumberB = Console.ReadLine();

                IOperation oper = OperationFactory.createOperate(strOperate);
                double result = oper.GetResult(double.Parse(strNumberA), double.Parse(strNumberB));
                Console.WriteLine("结果是：" + result.ToString());
                Console.ReadLine();
            }
            catch (Exception ex)
            {
                Console.WriteLine("您的输入有错：" + ex.Message);
                Console.ReadLine();
            }
        }
    }
}