Linq的delegate表达式,Insus.NET觉得它封装得好,让开发时简化了很多代码,而且容易阅读与检索。
比如,我们需要计算优惠给客户金额,打85%折,可以这样写:
using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Linq.Expressions;namespace Insus.NET.Utilities{ public class Class2 { public decimal Preferential(decimal amount) { return amount * (1 - 0.85m); //amount - amount * 0.85m; } }}
Source Code
应用方法:
下面我们使用delegate委托来实现:
运行结果:
接下来,Insus.NET还想使用一个表达式树的类型Expression<TDelegate>实现:
using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Linq.Expressions;namespace Insus.NET.Utilities{ public delegate decimal pref(decimal amount); public class Class2 { //public decimal Preferential(decimal amount) //{ // return amount * (1 - 0.85m); //amount - amount * 0.85m; //} // public pref Preferential11 = a => (a * (1 - 0.85m)); static Expression<pref> expr = amount => (amount - amount * 0.85m); public pref Preferential2 = expr.Compile(); }}
Source Code
方法引用运行结果:
原标题:LINQ的Expression与delegate表达式
关键词:linq