大话设计模式读书笔记（六）

工厂方法计算器结构图：

 

工厂方法计算器代码：

 

using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace 工厂模式 { class Program { static void Main(string[] args) { IFactory operFactory = new AddFactory(); Operation oper = operFactory.CreateOperation(); oper.NumberA = 1; oper.NumberB = 2; double result = oper.GetResult(); Console.WriteLine(result); } } 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; } } public class OperationAdd:Operation { public override double GetResult() { double result = 0; result = NumberA + NumberB; return result; } } public class OperationSub : Operation { public override double GetResult() { double result = 0; result = NumberA - NumberB; return result; } } public class OperationMul : Operation { public override double GetResult() { double result = 0; result = NumberA * NumberB; return result; } } 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; } } interface IFactory { Operation CreateOperation(); } class AddFactory : IFactory { public Operation CreateOperation() { return new OperationAdd(); } } class SubFactory : IFactory { public Operation CreateOperation() { return new OperationSub(); } } class MulFaction : IFactory { public Operation CreateOperation() { return new OperationMul(); } } class DivFaction : IFactory { public Operation CreateOperation() { return new OperationDiv(); } } }

工厂方法模式（Factory Method）：定义一个用于创建对象的接口，让子类决定实例化哪一个类。工厂方法使一个类的实例化延迟到其子类。

 

 

雷锋工厂

using System; using System.Collections.Generic; using System.Text; namespace 工厂方法_雷锋工厂 { class Program { static void Main(string[] args) { // //基本方式:薛磊风代表大学生学习雷锋 LeiFeng xueleifeng = new Undergraduate(); xueleifeng.BuyRice(); xueleifeng.Sweep(); xueleifeng.Wash(); LeiFeng student1 = new Undergraduate(); student1.BuyRice(); LeiFeng student2 = new Undergraduate(); student2.Sweep(); LeiFeng student3 = new Undergraduate(); student3.Wash(); //简单工厂模式 LeiFeng studentA = SimpleFactory.CreateLeiFeng("学雷锋的大学生"); studentA.BuyRice(); LeiFeng studentB = SimpleFactory.CreateLeiFeng("学雷锋的大学生"); studentB.Sweep(); LeiFeng studentC = SimpleFactory.CreateLeiFeng("学雷锋的大学生"); studentC.Wash(); //工厂方法模式 IFactory factory = new UndergraduateFactory(); LeiFeng student = factory.CreateLeiFeng(); student.BuyRice(); student.Sweep(); student.Wash(); Console.Read(); } } //雷锋 class LeiFeng { public void Sweep() { Console.WriteLine("扫地"); } public void Wash() { Console.WriteLine("洗衣"); } public void BuyRice() { Console.WriteLine("买米"); } } //学雷锋的大学生 class Undergraduate : LeiFeng { } //社区志愿者 class Volunteer : LeiFeng { } //简单雷锋工厂 class SimpleFactory { public static LeiFeng CreateLeiFeng(string type) { LeiFeng result = null; switch (type) { case "学雷锋的大学生": result = new Undergraduate(); break; case "社区志愿者": result = new Volunteer(); break; } return result; } } //雷锋工厂 interface IFactory { LeiFeng CreateLeiFeng(); } //学雷锋的大学生工厂 class UndergraduateFactory : IFactory { public LeiFeng CreateLeiFeng() { return new Undergraduate(); } } //社区志愿者工厂 class VolunteerFactory : IFactory { public LeiFeng CreateLeiFeng() { return new Volunteer(); } } }