Expression基础体验
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Linq.Expressions;
using System.Text;
using System.Threading.Tasks; namespace Unit
{
class T
{
public void Test()
{
Console.WriteLine("Test Class!");
}
}
class S
{
private List<int> ids = new List<int>();
public string Name { set; get; } public List<int> Ids { set { ids = value; } get { return ids; } }
}
class ET
{
public void Run()
{
//add
Add(, );//+
AddAssign(, );
Subtract(, );//-
SubtractAssign(,);
Multiply(,);
MultiplyAssign(,);
Divide(, );
DivideAssign(,);
Decrement();//i--;
Increment();//++
Modulo(); And(true, false); //&
AndAlso(true, false); //&&
Or(true, false);
OrElse(true, false); //||
LessThan(, );
Coalesce(, );
Coalesce(null, );
Is();
If();
IfElse();
Condition();
Switch();
Loop();
TypeAs();
Convert();
New();
NewArray();
NewArrayBounds();
ListInit();
ListBind();
}
/// <summary>
/// +
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void Add(int a,int b)
{
var left = Expression.Parameter(typeof(int));
var right = Expression.Parameter(typeof(int));
Expression exp = Expression.Add(left, right);
Expression<Func<int, int, int>> lambda = Expression.Lambda<Func<int, int, int>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
} public static int Add2(int a,int b)
{
return ;
} /// <summary>
/// 利用方法+
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void AddAssign(int a, int b)
{
var left = Expression.Parameter(typeof(int));
var right = Expression.Parameter(typeof(int));
Expression exp = Expression.AddAssign(left, right, this.GetType().GetMethod("Add2"));
Expression<Func<int, int, int>> lambda = Expression.Lambda<Func<int, int, int>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
}
/// <summary>
/// &
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void And(bool a, bool b)
{
var left = Expression.Parameter(typeof(bool));
var right = Expression.Parameter(typeof(bool));
Expression exp = Expression.And(left, right);
Expression<Func<bool, bool, bool>> lambda = Expression.Lambda<Func<bool, bool, bool>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
}
/// <summary>
/// &&
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void AndAlso(bool a, bool b)
{
var left = Expression.Parameter(typeof(bool));
var right = Expression.Parameter(typeof(bool));
Expression exp = Expression.AndAlso(left, right);
Expression<Func<bool, bool, bool>> lambda = Expression.Lambda<Func<bool, bool, bool>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
}
/// <summary>
/// |
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void Or(bool a, bool b)
{
var left = Expression.Parameter(typeof(bool));
var right = Expression.Parameter(typeof(bool));
Expression exp = Expression.Or(left, right);
Expression<Func<bool, bool, bool>> lambda = Expression.Lambda<Func<bool, bool, bool>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
}
/// <summary>
/// ||
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void OrElse(bool a, bool b)
{
var left = Expression.Parameter(typeof(bool));
var right = Expression.Parameter(typeof(bool));
Expression exp = Expression.OrElse(left, right);
Expression<Func<bool, bool, bool>> lambda = Expression.Lambda<Func<bool, bool, bool>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
} /// <summary>
/// -
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void Subtract(int a, int b)
{
var left = Expression.Parameter(typeof(int));
var right = Expression.Parameter(typeof(int));
Expression exp = Expression.Subtract(left, right);
Expression<Func<int, int, int>> lambda = Expression.Lambda<Func<int, int, int>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
}
private void SubtractAssign(int a, int b)
{
var left = Expression.Parameter(typeof(int));
var right = Expression.Parameter(typeof(int));
Expression exp = Expression.SubtractAssign(left, right, this.GetType().GetMethod("Add2"));
Expression<Func<int, int, int>> lambda = Expression.Lambda<Func<int, int, int>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
} /// <summary>
/// *
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void Multiply(int a, int b)
{
var left = Expression.Parameter(typeof(int));
var right = Expression.Parameter(typeof(int));
Expression exp = Expression.Multiply(left, right);
Expression<Func<int, int, int>> lambda = Expression.Lambda<Func<int, int, int>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
}
private void MultiplyAssign(int a, int b)
{
var left = Expression.Parameter(typeof(int));
var right = Expression.Parameter(typeof(int));
Expression exp = Expression.MultiplyAssign(left, right, this.GetType().GetMethod("Add2"));
Expression<Func<int, int, int>> lambda = Expression.Lambda<Func<int, int, int>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
}
/// <summary>
/// /
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void Divide(int a, int b)
{
var left = Expression.Parameter(typeof(int));
var right = Expression.Parameter(typeof(int));
Expression exp = Expression.Divide(left, right);
Expression<Func<int, int, int>> lambda = Expression.Lambda<Func<int, int, int>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
}
/// <summary>
/// a/=b
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void DivideAssign(int a, int b)
{
var left = Expression.Parameter(typeof(int));
var right = Expression.Parameter(typeof(int));
Expression exp = Expression.DivideAssign(left, right, this.GetType().GetMethod("Add2"));
Expression<Func<int, int, int>> lambda = Expression.Lambda<Func<int, int, int>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
}
/// <summary>
/// --
/// </summary>
/// <param name="a"></param>
private void Decrement(int a)
{
var left = Expression.Parameter(typeof(int));
Expression exp = Expression.Decrement(left);
Expression<Func<int, int>> lambda = Expression.Lambda<Func<int, int>>(exp, new ParameterExpression[] { left });
var l = lambda.Compile();
var r = l(a);
Console.WriteLine(r);
}
/// <summary>
/// ++
/// </summary>
/// <param name="a"></param>
private void Increment(int a)
{
var left = Expression.Parameter(typeof(int));
Expression exp = Expression.Increment(left);
Expression<Func<int, int>> lambda = Expression.Lambda<Func<int, int>>(exp, new ParameterExpression[] { left });
var l = lambda.Compile();
var r = l(a);
Console.WriteLine(r);
}
/// <summary>
/// >
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void LessThan(int a, int b)
{
var left = Expression.Parameter(typeof(int));
var right = Expression.Parameter(typeof(int));
Expression exp = Expression.LessThan(left, right);
Expression<Func<int, int, bool>> lambda = Expression.Lambda<Func<int, int, bool>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a,b);
Console.WriteLine(r);
}
/// <summary>
/// ??
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
private void Coalesce(int? a, int b)
{
var left = Expression.Parameter(typeof(int?));
var right = Expression.Parameter(typeof(int)); var right2 = Expression.Assign(right, Expression.Default(typeof(int)));
Expression exp = Expression.Coalesce(left, right2);
Expression<Func<int?, int, int>> lambda = Expression.Lambda<Func<int?, int, int>>(exp, new ParameterExpression[] { left, right });
var l = lambda.Compile();
var r = l(a, b);
Console.WriteLine(r);
} public static bool IsFalse(bool flag){
return false;
}
/// <summary>
/// is
/// </summary>
private void Is()
{
var v1 = Expression.Parameter(typeof(bool)); var v11 = Expression.Assign(v1,Expression.Constant(true));
var v2 = Expression.IsFalse(v1, this.GetType().GetMethod("IsFalse"));
Expression exp = Expression.IsFalse(v2);
var v3=Expression.TypeIs(Expression.Constant(new List<int>()),typeof(IList<int>));
Expression<Func<bool,bool>> lambda = Expression.Lambda<Func<bool,bool>>(exp, new ParameterExpression[] {v1 });
var l = lambda.Compile();
var r = l(true);
Console.WriteLine(r);
Expression<Func<bool>> lambda2 = Expression.Lambda<Func<bool>>(v3);
var l2 = lambda2.Compile();
Console.WriteLine(l2());
}
/// <summary>
/// if
/// </summary>
private void If()
{
var v1 = Expression.Variable(typeof(int),"a");
var v11 = Expression.Assign(v1, Expression.Constant());
var v2 = Expression.GreaterThan(v11, Expression.Constant());
Expression exp = Expression.IfThen(v2,Expression.Call(typeof(Console).GetMethod("WriteLine",new Type[]{typeof(int)}),v1));
Expression exp2 = Expression.Block(new[]{v1},exp);
Expression<Action> lambda = Expression.Lambda<Action>(exp2, new ParameterExpression[] { });
var l = lambda.Compile();
l();
} /// <summary>
/// if else
/// </summary>
private void IfElse()
{
var v1 = Expression.Variable(typeof(int), "a");
var v11 = Expression.Assign(v1, Expression.Constant());
var v2 = Expression.GreaterThan(v11, Expression.Constant());
Expression exp = Expression.IfThenElse(v2, Expression.Call(typeof(Console).GetMethod("WriteLine", new Type[] { typeof(string) }), Expression.Constant("True")), Expression.Call(typeof(Console).GetMethod("WriteLine", new Type[] { typeof(string) }), Expression.Constant("False")));
Expression exp2 = Expression.Block(new[] { v1 }, exp);
Expression<Action> lambda = Expression.Lambda<Action>(exp2, new ParameterExpression[] { });
var l = lambda.Compile();
l();
} /// <summary>
/// trueTest?ifTrue:ifFalse;
/// </summary>
private void Condition()
{
var v1 = Expression.Variable(typeof(int), "a");
var v11 = Expression.Assign(v1, Expression.Constant());
var v2 = Expression.GreaterThan(v1, Expression.Constant());
Expression exp = Expression.Condition(v2, Expression.Call(typeof(Console).GetMethod("WriteLine", new Type[] { typeof(string) }), Expression.Constant("True")), Expression.Call(typeof(Console).GetMethod("WriteLine", new Type[] { typeof(string) }), Expression.Constant("False")));
Expression exp2 = Expression.Block(new[] { v1 },v11, exp);
Expression<Action> lambda = Expression.Lambda<Action>(exp2, new ParameterExpression[] { });
var l = lambda.Compile();
l();
}
/// <summary>
/// switch
/// </summary>
/// <param name="i"></param>
private void Switch(int i)
{
var par = Expression.Parameter(typeof(int));
var target = Expression.Label(typeof(int),"a");
var exp = Expression.Switch(par, Expression.Break(target, Expression.Constant(-)), Expression.SwitchCase(Expression.Break(target, par), Expression.Constant()));
var lbl = Expression.Label(target, Expression.Constant());
var block = Expression.Block(exp,lbl);
Expression<Func<int, int>> lambda = Expression.Lambda<Func<int, int>>(block, new ParameterExpression[] { par });
var l = lambda.Compile();
Console.WriteLine(l(i));
}
/// <summary>
/// while(true){}
/// </summary>
/// <param name="i"></param>
private void Loop(int i)
{
var par = Expression.Parameter(typeof(int));
var ret = Expression.Variable(typeof(int), "ret");
var v11 = Expression.Assign(ret, Expression.Constant());
var lbl = Expression.Label(typeof(int));
var lbl2 = Expression.Label(lbl,Expression.Constant());
var block1 = Expression.Block(Expression.AddAssign(ret,par),Expression.SubtractAssign(par,Expression.Constant()));
var condition = Expression.IfThenElse(Expression.GreaterThan(par, Expression.Constant()),block1, Expression.Break(lbl, ret));
var block2 = Expression.Block(new[] { ret }, v11, Expression.Loop(condition), lbl2);// Expression.Block(new[] { ret }, v11, Expression.Loop(condition,lbl)) 可以达到一样的效果
Expression<Func<int, int>> lambda = Expression.Lambda<Func<int, int>>(block2, new ParameterExpression[] { par });
var l = lambda.Compile();
Console.WriteLine(l(i));
} /// <summary>
/// as
/// </summary>
private void TypeAs()
{
Expression s = Expression.Constant();
var t=Expression.TypeAs(s, typeof(object));
var call = Expression.Call(typeof(Console).GetMethod("WriteLine", new[] { typeof(int) }), Expression.Unbox(t, typeof(int)));
Expression<Action> lambda = Expression.Lambda<Action>(call);
var l=lambda.Compile();
l();
} /// <summary>
/// 强转 class定义TypeConverter,TypeConverterAttribute
/// </summary>
private void Convert()
{
Expression s = Expression.Constant(7.5);
var t = Expression.Convert(s, typeof(int));
var call = Expression.Call(typeof(Console).GetMethod("WriteLine", new[] { typeof(int) }),t);
Expression<Action> lambda = Expression.Lambda<Action>(call);
var l = lambda.Compile();
l();
} /// <summary>
/// %
/// </summary>
private void Modulo()
{
Expression s1 = Expression.Constant();
Expression s2 = Expression.Constant();
var t = Expression.Modulo(s1,s2); Expression<Func<int>> lambda = Expression.Lambda<Func<int>>(t);
var l = lambda.Compile();
Console.WriteLine(l());
} /// <summary>
/// new
/// </summary>
private void New()
{
Expression s = Expression.Constant();
var t = Expression.New(typeof(T));
var call = Expression.Call(t, typeof(T).GetMethod("Test"));
Expression<Action> lambda = Expression.Lambda<Action>(call);
var l = lambda.Compile();
l();
} /// <summary>
/// 初始化数组对象new int[]{7}
/// </summary>
private void NewArray()
{
Expression s = Expression.Constant();
var t = Expression.NewArrayInit(typeof(int),s);
var call = Expression.Call(t, typeof(int[]).GetProperty("Length").GetGetMethod());
Expression<Func<int>> lambda = Expression.Lambda<Func<int>>(call);
var l = lambda.Compile();
Console.WriteLine(l());
} /// <summary>
/// new int[7]
/// </summary>
private void NewArrayBounds()
{
Expression s = Expression.Constant();
var t = Expression.NewArrayBounds(typeof(int), s);
var call = Expression.Call(t, typeof(int[]).GetProperty("Length").GetGetMethod());
Expression<Func<int>> lambda = Expression.Lambda<Func<int>>(call);
var l = lambda.Compile();
Console.WriteLine(l());
}
/// <summary>
/// new List<int>(){5}
/// </summary>
private void ListInit()
{
Expression s = Expression.Constant();
var lst = Expression.New(typeof(List<int>));
var t = Expression.ListInit(lst,s);
var call = Expression.Call(t, typeof(List<int>).GetProperty("Count").GetGetMethod());
Expression<Func<int>> lambda = Expression.Lambda<Func<int>>(call);
var l = lambda.Compile();
Console.WriteLine(l());
}
/// <summary>
/// var s=new S();s.Ids.Add(5);s.Ids.Add(7);
/// </summary>
private void ListBind()
{
Type s = typeof(S);
var n=Expression.New(s);
var ids=s.GetProperty("Ids");
var l=typeof(List<int>);
var n2 = Expression.New(l);
var e1 = Expression.ElementInit(l.GetMethod("Add"), Expression.Constant());
var e2 = Expression.ElementInit(l.GetMethod("Add"), Expression.Constant());
var lst = Expression.ListBind(ids,e1,e2);
var init=Expression.MemberInit(n,lst);
Expression<Func<S>> lambda = Expression.Lambda<Func<S>>(init);
var ln = lambda.Compile();
var o = ln();
Console.WriteLine(o);
}
/// <summary>
/// L_0000: ldarg.1
/// L_0001: call void [mscorlib]System.Console::WriteLine(int32)
/// L_0006: ldarg.s j2
/// L_0008: call void [mscorlib]System.Console::WriteLine(int32)
/// L_000d: ret
/// </summary>
private void TestArgs(int a, int b, int c, int d, int e, int f, int g, int h, int i, int j, int a1, int b1, int c1, int d1, int e1, int f1, int g1, int h1, int i1, int j1, int a2, int b2, int c2, int d2, int e2, int f2, int g2, int h2, int i2, int j2)
{ Console.WriteLine(a);
Console.WriteLine(j2);
}
}
}
Expression基础体验的更多相关文章
- Java 8 新特性之 Stream 流基础体验
Java 8 新特性之 Stream 流基础体验 package com.company; import java.util.ArrayList; import java.util.List; imp ...
- 零基础学习python 你该怎么做
本人文科生,回顾自己近 2 年的Python 自学经历,有一些学习心得和避坑经验分享给大家,让大家在学习 Python 的过程中少走一些弯路!减少遇到不必要的学习困难! 首先,最开始最大的困难应该就是 ...
- CI Weekly #4 | 不同规模的团队，如何做好持续集成？
CI Weekly 围绕『 软件工程效率提升』 进行一系列技术内容分享,包括国内外持续集成.持续交付,持续部署.自动化测试. DevOps 等实践教程.工具与资源,以及一些工程师文化相关的程序员 Ti ...
- MVC验证01-基础、远程验证
本文体验MVC服务端和客户端验证.主要涉及:※ 基础验证※ 远程验证1个或多个属性及注意点 基础体验 创建MVC4的Internet项目,本身包含了基本的Model,Views,Controller. ...
- H5 App设计者需要注意的21条禁忌
我们通常在做H5 APP设计的过程中,遇到很多看似很小,且很容易被忽略的问题,正是这些小问题,一次次的撩拨用户的耐心,让用户对你的APP心生怨念.现在WeX5君呕血为大家整理出H5 APP设计的21条 ...
- android 类似QQ底部输入框弹出键盘和面板冲突 布局闪动处理方案(转)
先看下效果 差不多就是解决这种冲突,布局闪动的 作者的githup :https://github.com/Jacksgong/JKeyboardPanelSwitch Android键盘面板冲突 布 ...
- 01Vue数据双向绑定
Vue作为前端MV*架构,Vue.js (读音 /vjuː/,类似于 view) 是一套构建用户界面的渐进式框架.与其他重量级框架不同的是,Vue 采用自底向上增量开发的设计. Vue 的核心库只关注 ...
- QQ音乐的动效歌词是如何实践的？
本文由云+社区发表 作者:QQ音乐技术团队 一. 背景 1. 现状 歌词浏览已经成为音乐app的标配,展示和动画效果也基本上大同小异,主要是单行的逐字染色的卡拉OK效果和多行的滚动效果.当然,我们也不 ...
- Java 11 正式发布，这 8 个逆天新特性教你写出更牛逼的代码
美国时间 09 月 25 日,Oralce 正式发布了 Java 11,这是据 Java 8 以后支持的首个长期版本. 为什么说是长期版本,看下面的官方发布的支持路线图表. 可以看出 Java 8 扩 ...
随机推荐
- 《linux就该这么学》第十四节课：第13章，部署DNS域名解析服务（bind服务）
(借鉴请改动) 第十二章收尾 12.2.nfs网络文件系统 RHEL7默认安装了nfs,配置文件在 /etc/export 写入格式:共享目录 允许的客户端(参数) ro ...
- 常见的四种文本自动分词详解及IK Analyze的代码实现
以下解释来源于网络-百度百科 1.word分词器 word分词 [1] 是一个Java实现的分布式的中文分词组件,提供了多种基于词典的分词算法,并利用ngram模型来消除歧义.能准确识别英文.数字, ...
- linux 系统管理11 ——系统安全及应用
一.基本安全措施 1.系统账号清理 (1).将非登陆用户的shell设为/sbin/nologin 方法一.usermod -s 方法二.chsh命令,交互式修改 方法三.chsh -s usermo ...
- 【JavaScript】学习中遇到的一些问题
一.JavaScript中没法直接比较两个object和array是否相等
- 为fastdfs文件服务器新增一个storage
一.前言: 前期,已经搭建好了一套fastdfs文件服务器,一个tracker和一个storage,且部署在同一台服务器上,已经正式投入运行快半年了,1T的空间现在只剩下100G容量了,现在需要扩容, ...
- SSM(Spring4.x.x+SpringMVC4.x.x+Mybatis3.4.x)框架整合
本文是参考SSM框架——详细整合教程(Spring+SpringMVC+MyBatis)修改而来的 一.环境 1. Myeclipse2016 2. Mysql 二.具体步骤 1. 整合Spring和 ...
- (cvpr 2018)Technology details of SMRD
1．摘要 近年来,深度卷积神经网络(CNN)方法在单幅图像超分辨率(SISR)领域取得了非常大的进展.然而现有基于 CNN 的 SISR 方法主要假设低分辨率(LR)图像由高分辨率(HR)图像经过双三 ...
- WebStorm过期解决方法
第一步:先删除C:\Users\本机用户名\.WebStorm2016.3\config文件中eval文件. 第二步:打开webstrom 如图,填写许可证激活码:http://idea.imsxm. ...
- SAP 查询分析器，查询报表自动生成，SQL查询测试实现说明（转）
在日常的SAP开发和应用中,经常需要通过查询SAP数据表来处理日常业务,比如:数据对账.报表SQL测试.SAP查询功能开发等.通过开发SAP查询分析器,SAP实施和开发人员,可以在较短的时间内查询到需 ...
- 软件测试1gkd
通过老师课上的讲解以及对书本和百度百科的学习,我对软件测试有如下的理解. 软件开发的最基本要求是按时.高质量地发布软件产品,而软件测试是软件质量保证的最重要的手段之一.在整个软件生命周 ...