switch case 多个处理方式涉及到销售优惠折扣方案处理

定义一个销售接口                                                                                               ICarSalsecs
 public interface ICarSalsecs
    {
        /// <summary>
        /// 优惠折扣方案接口
        /// </summary>
        /// <param name="policType">打折类型</param>
        /// <param name="SalsePrice">折前价格</param>
        /// <returns></returns>
        decimal Discount(short policType, decimal SalsePrice);
    }

定义一个销售类  

public class CarSalse: ICarSalsecs
    {
        private readonly Dictionary<short, Func<decimal, decimal>> _dic;
        public CarSalse()
        {
            _dic = new Dictionary<short, Func<decimal, decimal>>
            {
                {0, m => m * (decimal)0.1},
                {1, m => m * (decimal)0.3},
                {2, m => m * (decimal)0.5},
                {3, m => m * (decimal)0.7},
                {4, m => m * (decimal)0.9}
            };
        }
       
     
        //把各种打折方案封装在字典集合中。
        public decimal Discount(short policyType, decimal SalsePrice)
        {
            if (_dic.ContainsKey(policyType))
            {
                return _dic[policyType].Invoke(SalsePrice);
            }
            return SalsePrice / 2;
        }
    }
    /// <summary>
    /// 折扣枚举类型
    /// </summary>
    public enum PolicyType
    {
        一折 = 0,
        三折 = 1,
        五折 = 2,
        七折 = 3,
        九折 = 4
    }

调用方法实现折扣处理
static void Main(string[] args)
        {
            Console.WriteLine("请输入打折策略，0表示1折，1表示3折，2表示5折，3表示7折，4表示9折：");
            string policy = Console.ReadLine();
            decimal SalsePrice = (decimal)10000.00;
            Console.WriteLine("打折前的价格为：" + SalsePrice);
            CarSalse Salse = new CarSalse();
            if (!string.IsNullOrWhiteSpace(policy))
            { 
            Console.WriteLine("打折后的价格为：" + Salse.Discount(short.Parse(policy), SalsePrice));
            }
            Console.ReadKey();
        }