C# 设计模式，简单工厂

C# 实现计算机功能 （封装，继承，多态）

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

namespace 简单工厂 {
    class Program {
        
        static void Main(string[] args) {
            Operation op = Facotry.createFactory("+");
            op.Number1 = 10;
            op.Number2 = 20;
            int result = op.getResult();
            Console.WriteLine(op.ToString());
            Console.ReadKey();
        }
        class Operation { //父类，封装
            protected int number1;
            protected int number2;

            public int Number1 {
                get { return number1; }
                set { number1 = value; }
            }
            public int Number2 {
                get { return number2; }
                set { number2 = value; }
            }
            public virtual int getResult() {
                int result = 0;
                return result;
            }
        }
        class OperationAdd : Operation {
            public override int getResult() {
                return number1 + number2;
            }
        }

        class OperationSub : Operation {
            public override int getResult() {
                return number1-number2;
            }
        }
        
        class Facotry {
            public static Operation createFactory(string ope) {
                Operation op = null;
                switch (ope) {
                    case "+":
                        op = new OperationAdd();
                        break;
                    case "-":
                        op = new OperationSub();
                        break;
                }
                return op;
            }
        }
    }
}