大话设计模式－简单工厂模式(1)

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

namespace SimpleFactory
{
    /// <summary>
    /// 抽象父类
    /// </summary>
    public class Operation
    {
        private double numberA = 0;
        private double numberB = 0;

        public double NumberA
        {
            get { return numberA; }
            set { numberA = value; }
        }

        public double NumberB
        {
            get { return numberB; }
            set { numberB = value; }
        }

        public virtual double GetResult()
        {
            double result = 0;
            return result;
        }
    }
}

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

namespace SimpleFactory
{
    /// <summary>
    /// 简单工厂模式
    /// </summary>
    public class OperationFactory
    {
        public static Operation CreateOperate(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;
        }
    }
}

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

namespace SimpleFactory
{
    public class OperationAdd : Operation
    {
        public override double GetResult()
        {
            double result = 0;
            result = NumberA + NumberB;
            return result;
        }
    }
}

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

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

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

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

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

namespace SimpleFactory
{
    public class OperationDiv:Operation
    {
        public override double GetResult()
        {
            double result = 0;
            if (NumberB == 0)
            {
                throw new Exception("除数不能为0");
            }
            result = NumberA / NumberB;
            return result;
        }
    }
}

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

namespace SimpleFactory
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.Write("请输入数字A:");
            string numberA = Console.ReadLine();
            Console.Write("请输入运算符号(+,-,*,/):");
            string strOperate = Console.ReadLine();
            Console.Write("请输入数字B:");
            string numberB = Console.ReadLine();

            Operation oper;
            oper = OperationFactory.CreateOperate(strOperate);
            oper.NumberA = Convert.ToDouble(numberA);
            oper.NumberB = Convert.ToDouble(numberB);

            double result = oper.GetResult();

            Console.Write("计算结果是:" + result.ToString());
            Console.ReadLine();
        }
    }
}