通过策略模式来重构优化代码里面的switch/case分支代码。极大程度上提高了程序的扩展性。当然,如果分支比较多,每次都需要新增加一个类,这的确是有点麻烦,可以考虑使用反射来实现。
代码:
namespace DP
{
public enum State
{
Alaska,
NewYork,
Florida
}
// 抽象
//public interface IShippingInfo
//{
// decimal Calculate(State state);
//}
public class CalculateShippingAmount
{
public CalculateShippingAmount(IDictionary<State, IGetShippingAmount> dic) => _dic = dic;
private IDictionary<State, IGetShippingAmount> _dic { get; set; }
public decimal Calculate(State state) => _dic[state].GetAmount();
}
public interface IGetShippingAmount
{
decimal GetAmount();
}
#region 具体地址的实现
// 具体
public class GetAlaskaShippingAmount : IGetShippingAmount
{
public decimal GetAmount() => 15;
}
public class GetNewYorkShippingAmount : IGetShippingAmount
{
public decimal GetAmount() => 10;
}
public class GetFloridaShippingAmount : IGetShippingAmount
{
public decimal GetAmount() => 3;
}
#endregion
}
调用:
#region 策略模式重构 switch...case...
static void SwitchToStrategy()
{
var dic = new Dictionary<State, IGetShippingAmount>
{
{State.Alaska, new GetAlaskaShippingAmount() },
{State.Florida, new GetFloridaShippingAmount() },
{State.NewYork, new GetNewYorkShippingAmount() }
};
var calculate = new CalculateShippingAmount(dic);
var result = calculate.Calculate(State.Florida);
Console.WriteLine($"{State.Florida.ToString()}返回{result}");
}
#endregion
原文地址:https://www.cnblogs.com/zhiyong-ITNote/p/10981236.html
时间: 2024-11-05 22:55:19