设计模式》模板方法

例子

• 妈妈买菜，爸爸买菜，自己买菜

    public abstract class AbsBuyVegetable
    {
        public virtual void BuyVegetable()
        {
            BuyShuCai();
            BuyMeat();
            BuyComplete();
        }

        /// <summary>
        /// 买蔬菜
        /// </summary>
        protected virtual void BuyShuCai()
        {
            Console.WriteLine("随便买点蔬菜");
        }

        /// <summary>
        /// 买肉
        /// </summary>
        protected virtual void BuyMeat()
        {
            Console.WriteLine("随便买点肉");
        }


        /// <summary>
        /// 购买完成回调
        /// </summary>
        protected virtual void BuyComplete()
        {
        }
    }

    public class BaBaBuyVegetable : AbsBuyVegetable
    {
        protected override void BuyMeat()
        {
            Console.WriteLine("爸爸买肉食：鱼");
        }

        protected override void BuyShuCai()
        {
            Console.WriteLine("爸爸买蔬菜：海带");
        }

        protected override void BuyComplete()
        {
            Console.WriteLine("爸爸买菜完毕");
        }
    }

    public class MaMaBuyVegetable : AbsBuyVegetable
    {
        protected override void BuyMeat()
        {
            Console.WriteLine("妈妈买肉食：羊肉，牛肉");
        }

        protected override void BuyShuCai()
        {
            Console.WriteLine("妈妈买蔬菜：青菜");
        }

        protected override void BuyComplete()
        {
            Console.WriteLine("妈妈买菜完毕");
        }
    }

    public class OwnerBuyVegetable : AbsBuyVegetable
    {
        protected override void BuyMeat()
        {
            Console.WriteLine("自己买肉食：大羊排");
        }

        protected override void BuyShuCai()
        {
            Console.WriteLine("自己买蔬菜：不买");
        }

        protected override void BuyComplete()
        {
            Console.WriteLine("自己买菜完毕");
        }
    }

• 公司-》老板的工作，产品的工作，技术的工作

    public abstract class AbsCompanyWork
    {
        public void Work()
        {
            ShangWu();
            XiaWu();
        }


        protected virtual void ShangWu()
        {
            Console.WriteLine("上午：啥也不干");
        }

        protected virtual void XiaWu()
        {
            Console.WriteLine("上午：啥也不干");
        }
    }

    public class Boss : AbsCompanyWork
    {
        protected override void ShangWu()
        {
            Console.WriteLine("上午：睡觉");
        }

        protected override void XiaWu()
        {
            Console.WriteLine("下午：数钱");
        }
    }

    public class ChanPing : AbsCompanyWork
    {
        protected override void ShangWu()
        {
            Console.WriteLine("上午：画需求");
        }

        protected override void XiaWu()
        {
            Console.WriteLine("下午：与程序员吵架");
        }
    }

    public class JiShu : AbsCompanyWork
    {
        protected override void ShangWu()
        {
            Console.WriteLine("上午：敲代码");
        }

        protected override void XiaWu()
        {
            Console.WriteLine("下午：改Bug");
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            // BuyVegetableTest();
            
            new Boss().Work();
            new ChanPing().Work();
            new JiShu().Work();
        }

        private static void BuyVegetableTest()
        {
            new OwnerBuyVegetable().BuyVegetable();
            new MaMaBuyVegetable().BuyVegetable();
            new BaBaBuyVegetable().BuyVegetable();
        }
    }

个人总结

算法的整体步骤很固定，但其中个别部分易变时，这时候可以使用模板方法模式，将容易变的部分抽象出来，供子类实现。