LINQ简介

语言集成查询（英语：Language Integrated Query，缩写：LINQ），发音"link"，是微软的一项技术，新增一种自然查询的SQL语法到.NET Framework的编程语言中，当前可支持C#以及Visual Basic .NET语言。2007年11月19日随.NET Framework 3.5发布了LINQ技术。 — from 百度百科

在C#中使用LINQ之前的准备

使用LINQ之前必须要有数据，所以刘叔需要搞几个class，并弄点数据来。在这里分别建立三个class，并且每个class都会有一个static方法GetList()来创建模拟数据。在这里感谢菜鸟教程提供数据。

Category类用于存放分类的数据

using System.Collections.Generic;namespace LINQcsdn {public class Category {public int CategoryId { get; private set; }public string CategoryName { get; private set; }public Category(int id, string name) {CategoryId = id;CategoryName = name;}public Category(): this(0, "") { }public override string ToString() {string result = "{";result += "\"category_id\": " + $"{CategoryId}" + ", ";result += "\"category_name\": " + $"\"{CategoryName}\"";result += "}";return result;}public static List<Category> GetList() {return new List<Category>() {new Category(1, "HTML / CSS"),new Category(2, "JavaScript"),new Category(3, "服务端"),new Category(4, "数据库"),new Category(5, "移动端"),new Category(6, "XML 教程"),new Category(7, "ASP.NET"),new Category(8, "Web Service"),new Category(9, "开发工具"),new Category(10, "网站建设")};}}
}

Course类用于存放课程数据

using System.Collections.Generic;namespace LINQcsdn {public class Course {public int CourseId { get; private set; }public int CategoryId { get; private set; }public string CourseUrl { get; private set; }public string CourseName { get; private set; }public string CourseIntro { get; private set; }public Course(int id, int cId, string url, string name, string intro) {CourseId = id;CategoryId = cId;CourseUrl = url;CourseName = name;CourseIntro = intro;}public Course() : this(0, 0, "", "", "") { }public override string ToString() {string result = "{";result += "\"course_id\": " + $"{CourseId}" + ", ";result += "\"category_id\": " + $"{CategoryId}" + ", ";result += "\"course_name\": " + $"\"{CourseName}\"" + ", ";result += "\"course_intro\": " + $"\"{CourseIntro}\"" + ", ";result += "\"course_url\": " + $"\"{CourseUrl}\"";result += "}";return result;}public static List<Course> GetList() {return new List<Course>() {new Course(1, 1, "https://www.runoob.com/html/html-tutorial.html", "【学习 HTML】", "HTML，即超文本标记语言（Hyper Text Markup Language）"),new Course(2, 1, "https://www.runoob.com/html/html5-intro.html", "【学习 HTML5】", "HTML5 是下一代 HTML 标准"),new Course(3, 1, "https://www.runoob.com/css/css-tutorial.html", "【学习 CSS】", "层叠样式表（Cascading StyleSheet）"),new Course(4, 1, "https://www.runoob.com/css3/css3-tutorial.html", "【学习 CSS3】", "CSS3是CSS技术的升级版本"),new Course(5, 1, "https://www.runoob.com/bootstrap/bootstrap-tutorial.html", "【学习 Bootstrap3】", "Bootstrap，来自 Twitter，是目前最受欢迎的前端框架"),new Course(6, 1, "https://www.runoob.com/bootstrap4/bootstrap4-tutorial.html", "【学习 Bootstrap4】", "Bootstrap4 目前是 Bootstrap 的最新版本"),new Course(7, 1, "https://www.runoob.com/font-awesome/fontawesome-tutorial.html", "【学习 Font Awesome】", "Font Awesome 是一套绝佳的图标字体库和CSS框架。"),new Course(8, 1, "https://www.runoob.com/foundation/foundation-tutorial.html", "【学习 Foundation】", "Foundation 用于开发响应式的 HTML, CSS and JavaScript 框架"),new Course(9, 2, "https://www.runoob.com/js/js-tutorial.html", "【学习 JavaScript】", "JavaScript 是 Web 的编程语言"),new Course(10, 2, "https://www.runoob.com/htmldom/htmldom-tutorial.html", "【学习 HTML DOM】", "HTML DOM 定义了访问和操作 HTML 文档的标准方法"),new Course(11, 2, "https://www.runoob.com/jquery/jquery-tutorial.html", "【学习 jQuery】", "jQuery 是一个 JavaScript 库"),new Course(12, 2, "https://www.runoob.com/angularjs/angularjs-tutorial.html", "【学习 AngularJS】", "AngularJS 通过新的属性和表达式扩展了 HTML"),new Course(13, 2, "https://www.runoob.com/angularjs2/angularjs2-tutorial.html", "【学习 AngularJS2】", "AngularJS2 是一款开源JavaScript库，由Google维护。"),new Course(14, 2, "https://www.runoob.com/vue2/vue-tutorial.html", "【学习 Vue.js】", "Vue.js 是一套构建用户界面的渐进式框架。"),new Course(15, 2, "https://www.runoob.com/react/react-tutorial.html", "【学习 React】", "React 是一个用于构建用户界面的 JAVASCRIPT 库"),new Course(16, 2, "https://www.runoob.com/typescript/ts-tutorial.html", "【学习 TypeScript】", "TypeScript 是 JavaScript 的一个超集，支持 ECMAScript 6 标准"),new Course(17, 2, "https://www.runoob.com/jqueryui/jqueryui-tutorial.html", "【学习 jQuery UI】", "jQuery UI 是建立在 jQuery上的一组用户界面交互、特效、小部件及主题"),new Course(18, 2, "https://www.runoob.com/jeasyui/jqueryeasyui-tutorial.html", "【学习 jQuery EasyUI 】", "jQuery EasyUI 是一个基于 jQuery 的框架，集成了各种用户界面插件"),new Course(19, 2, "https://www.runoob.com/nodejs/nodejs-tutorial.html", "【学习 Node.js】", "Node.js 是运行在服务端的 JavaScript"),new Course(20, 2, "https://www.runoob.com/ajax/ajax-tutorial.html", "【学习 AJAX】", "AJAX = Asynchronous JavaScript and XML（异步的 JavaScript 和 XML）"),new Course(21, 2, "https://www.runoob.com/json/json-tutorial.html", "【学习 JSON】", "JSON 是存储和交换文本信息的语法"),new Course(22, 2, "https://www.runoob.com/echarts/echarts-tutorial.html", "【学习 Echarts】", "ECharts 是一个使用 JavaScript 实现的开源可视化库"),new Course(23, 2, "https://www.runoob.com/highcharts/highcharts-tutorial.html", "【学习 Highcharts】", "Highcharts 是一个用纯JavaScript编写的一个图表库"),new Course(24, 2, "https://www.runoob.com/googleapi/google-maps-basic.html", "【学习 Google 地图】", "Google 地图接口使用说明"),new Course(25, 3, "https://www.runoob.com/python3/python3-tutorial.html", "【学习 Python】", "Python3.x 版本，未来主流版本。"),new Course(26, 3, "https://www.runoob.com/python/python-tutorial.html", "【学习 Python2.x】", "Python 是一种面向对象、解释型计算机程序设计语言"),new Course(27, 3, "https://www.runoob.com/linux/linux-tutorial.html", "【学习 Linux】", "Linux是一套免费使用和自由传播的类Unix操作系统"),new Course(28, 3, "https://www.runoob.com/docker/docker-tutorial.html", "【学习 Docker】", "Docker 是一个开源的应用容器引擎，基于 Go 语言"),new Course(29, 3, "https://www.runoob.com/ruby/ruby-tutorial.html", "【学习 Ruby】", "一种为简单快捷的面向对象编程（面向对象程序设计）而创的脚本语言"),new Course(30, 3, "https://www.runoob.com/java/java-tutorial.html", "【学习 Java】", "一种可以撰写跨平台应用软件的面向对象的程序设计语言"),new Course(31, 3, "https://www.runoob.com/c/c-tutorial.html", "【学习 C】", "一门通用计算机编程语言"),new Course(32, 3, "https://www.runoob.com/cplusplus/cpp-tutorial.html", "【学习 C++】", "C++是在C语言的基础上开发的一种通用编程语言"),new Course(33, 3, "https://www.runoob.com/perl/perl-tutorial.html", "【学习 Perl】", "Perl 是高级、通用、直译式、动态的程序语言"),new Course(34, 3, "https://www.runoob.com/servlet/servlet-tutorial.html", "【学习 Servlet 】", "运行在 Web 服务器或应用服务器上的程序"),new Course(35, 3, "https://www.runoob.com/jsp/jsp-tutorial.html", "【学习 JSP】", "JSP与PHP、ASP、ASP.NET等语言类似，运行在服务端的语言"),new Course(36, 3, "https://www.runoob.com/lua/lua-tutorial.html", "【学习 Lua】", "Lua 是一种轻量小巧的脚本语言，用标准C语言编写并以源代码形式开放"),new Course(37, 3, "https://www.runoob.com/rust/rust-tutorial.html", "【学习 Rust】", "Rust 语言是一种高效、可靠的通用高级语言"),new Course(38, 3, "https://www.runoob.com/r/r-tutorial.html", "【学习 R】", "R 语言是为数学研究工作者设计的一种数学编程语言"),new Course(39, 3, "https://www.runoob.com/scala/scala-tutorial.html", "【学习 Scala】", "Scala 是一门多范式（multi-paradigm）的编程语言。"),new Course(40, 3, "https://www.runoob.com/go/go-tutorial.html", "【学习 Go】", "Go语言是谷歌推出的一种全新的编程语言"),new Course(41, 3, "https://www.runoob.com/php/php-tutorial.html", "【学习 PHP】", "PHP 是一种通用开源脚本语言"),new Course(42, 3, "https://www.runoob.com/django/django-tutorial.html", "【学习 Django】", "Django是一个开放源代码的Web应用框架，由Python写成"),new Course(43, 3, "https://www.runoob.com/design-pattern/design-pattern-tutorial.html", "【设计模式】", "设计模式代表了最佳的实践，通常被有经验的面向对象的软件开发人员所采用"),new Course(44, 3, "https://www.runoob.com/regexp/regexp-tutorial.html", "【正则表达式】", "正则表达式是对字符串操作的一种逻辑公式"),new Course(45, 3, "https://www.runoob.com/maven/maven-tutorial.html", "【学习 Maven】", "Maven 是一个项目管理工具，可以对 Java 项目进行构建、依赖管理。"),new Course(46, 3, "https://www.runoob.com/numpy/numpy-tutorial.html", "【学习 NumPy】", "NumPy 是 Python 语言的一个扩展程序库，支持大量的维度数组与矩阵运算。"),new Course(47, 3, "https://www.runoob.com/asp/asp-tutorial.html", "【学习 ASP】", "ASP（Active Server Pages 动态服务器页面）是一种生成动态交互性网页的强有力工具"),new Course(48, 3, "https://www.runoob.com/appml/appml-tutorial.html", "【学习 AppML】", "AppML 是一个为web应用程序设计的HTML扩展框"),new Course(49, 3, "https://www.runoob.com/vbscript/vbscript-tutorial.html", "【学习 VBScript】", "一种微软环境下的轻量级的解释型语言"),new Course(50, 4, "https://www.runoob.com/sql/sql-tutorial.html", "【学习 SQL】", "结构化查询语言(Structured Query Language)"),new Course(51, 4, "https://www.runoob.com/mysql/mysql-tutorial.html", "【学习 Mysql】", "MySQL是一个关系型数据库管理系统"),new Course(52, 4, "https://www.runoob.com/postgresql/postgresql-tutorial.html", "【学习 PostgreSQL】", "PostgreSQL 是一个免费的对象-关系数据库服务器(ORDBMS)"),new Course(53, 4, "https://www.runoob.com/sqlite/sqlite-tutorial.html", "【学习 SQLite】", "一款轻型的数据库"),new Course(54, 4, "https://www.runoob.com/mongodb/mongodb-tutorial.html", "【学习 MongoDB】", "Mongo DB 是目前在IT行业非常流行的一种非关系型数据库(NoSql)"),new Course(55, 4, "https://www.runoob.com/redis/redis-tutorial.html", "【学习 Redis】", "一个高性能的key-value数据库"),new Course(56, 4, "https://www.runoob.com/Memcached/Memcached-tutorial.html", "【学习 Memcached】", "Memcached是一个自由开源的，高性能，分布式内存对象缓存系统。"),new Course(57, 5, "https://www.runoob.com/w3cnote/android-tutorial-intro.html", "【学习 Android】", "Android 是一种基于Linux的自由及开放源代码的操作系统，主要使用于移动设备"),new Course(58, 5, "https://www.runoob.com/swift/swift-tutorial.html", "【学习 Swift】", "Swift 是一种支持多编程范式和编译式的编程语言,用于开发 iOS，OS X 和 watchOS应用程序。"),new Course(59, 5, "https://www.runoob.com/jquerymobile/jquerymobile-tutorial.html", "【学习 jQuery Mobile】", "jQuery Mobile是jQuery 在手机上和平板设备上的版本"),new Course(60, 5, "https://www.runoob.com/ionic/ionic-tutorial.html", "【学习 ionic】", "ionic 是一个强大的 HTML5 应用程序开发框架(HTML5 Hybrid Mobile App Framework )。"),new Course(61, 5, "https://www.runoob.com/kotlin/kotlin-tutorial.html", "【学习 Kotlin】", "在 Java 虚拟机上运行的静态类型编程语言，Android 官方开发语言"),new Course(62, 6, "https://www.runoob.com/xml/xml-tutorial.html", "【学习 XML】", "XML 被设计用来传输和存储数据"),new Course(63, 6, "https://www.runoob.com/dtd/dtd-tutorial.html", "【学习 DTD】", "DTD（文档类型定义）的作用是定义 XML 文档的合法构建模块"),new Course(64, 6, "https://www.runoob.com/dom/dom-tutorial.html", "【学习 XML DOM】", "XML DOM 定义访问和操作XML文档的标准方法"),new Course(65, 6, "https://www.runoob.com/xsl/xsl-tutorial.html", "【学习 XSLT】", "XSL 是一个 XML 文档的样式表语言，XSLT 指 XSL 转换"),new Course(66, 6, "https://www.runoob.com/xpath/xpath-tutorial.html", "【学习 XPath】", "XPath 是一门在 XML 文档中查找信息的语言"),new Course(67, 6, "https://www.runoob.com/xquery/xquery-tutorial.html", "【学习 XQuery】", "XQuery 被设计用来查询 XML 数据"),new Course(68, 6, "https://www.runoob.com/xlink/xlink-tutorial.html", "【学习 XLink】", "XLink 定义在 XML 文档中创建超级链接的标准方法"),new Course(69, 6, "https://www.runoob.com/xlink/xlink-tutorial.html", "【学习 XPointer】", "XPointer是在可扩展标志语言（XML）文件中定位数据的一种语言"),new Course(70, 6, "https://www.runoob.com/schema/schema-tutorial.html", "【学习 XML Schema】", "XML Schema 描述了 XML文档的结构"),new Course(71, 6, "https://www.runoob.com/xslfo/xslfo-tutorial.html", "【学习 XSL-FO】", "XSL-FO 指可扩展样式表语言格式化对象"),new Course(72, 6, "https://www.runoob.com/svg/svg-tutorial.html", "【学习 SVG】", "SVG 使用 XML 格式定义图像"),new Course(73, 7, "https://www.runoob.com/aspnet/aspnet-tutorial.html", "【学习 ASP.NET】", "ASP.NET 是一个使用 HTML、CSS、JavaScript 和服务器脚本创建网页和网站的开发框架"),new Course(74, 7, "https://www.runoob.com/csharp/csharp-tutorial.html", "【学习 C#】", "C# 是一个简单的、现代的、通用的、面向对象的编程语言"),new Course(75, 7, "https://www.runoob.com/aspnet/webpages-intro.html", "【学习 Web Pages】", "Web Pages 是三种网页编程模型中的一种，用于创建网站和web 应用程序"),new Course(76, 7, "https://www.runoob.com/aspnet/razor-intro.html", "【学习 Razor】", "Razor 是一种标记语法，可以让您将基于服务器的代码（Visual Basic 和 C#）嵌入到网页中"),new Course(77, 7, "https://www.runoob.com/aspnet/mvc-intro.html", "【学习 MVC】", "MVC（Model View Controller 模型-视图-控制器）"),new Course(78, 7, "https://www.runoob.com/aspnet/aspnet-intro.html", "【学习 Web Forms】", "Web Forms 是三种创建 ASP.NET 网站和 Web 应用程序的编程模式中的一种"),new Course(79, 8, "https://www.runoob.com/webservices/webservices-tutorial.html", "【学习 Web Service】", "Web Service 脚本平台需支持 XML + HTTP"),new Course(80, 8, "https://www.runoob.com/wsdl/wsdl-tutorial.html", "【学习 WSDL】", "WSDL是一门基于 XML 的语言，用于描述 Web Service 以及如何对它们进行访问"),new Course(81, 8, "https://www.runoob.com/soap/soap-tutorial.html", "【学习 SOAP】", "SOAP 是一种简单的基于 XML 的协议，它使应用程序通过 HTTP 来交换信息"),new Course(82, 8, "https://www.runoob.com/rss/rss-tutorial.html", "【学习 RSS】", "RSS基于XML标准，在互联网上被广泛采用的内容包装和投递协议"),new Course(83, 8, "https://www.runoob.com/rdf/rdf-tutorial.html", "【学习 RDF】", "DF(资源描述框架)是描述网络资源的 W3C 标准"),new Course(84, 9, "https://www.runoob.com/eclipse/eclipse-tutorial.html", "【学习 Eclipse】", "Eclipse 是一个开放源代码的、基于 Java 的可扩展开发平台"),new Course(85, 9, "https://www.runoob.com/git/git-tutorial.html", "【学习 Git】", "Git是一个开源的分布式版本控制系统，用于敏捷高效地处理任何或小或大的项目"),new Course(86, 9, "https://www.runoob.com/svn/svn-tutorial.html", "【学习 Svn】", "SVN 是一个开放源代码的版本控制系统"),new Course(87, 9, "https://www.runoob.com/markdown/md-tutorial.html", "【学习 Markdown】", "Markdown 是一种轻量级标记语"),new Course(88, 10, "https://www.runoob.com/http/http-tutorial.html", "【学习 HTTP】", "HTTP协议（HyperText Transfer Protocol，超文本传输协议）是因特网上应用最为广泛的一种网络传输协议"),new Course(89, 10, "https://www.runoob.com/web/web-buildingprimer.html", "【网站建设指南】", "网站建设指导课程"),new Course(90, 10, "https://www.runoob.com/browsers/browser-information.html", "【浏览器信息】", "对于网站开发人员来说，浏览器信息和统计数据都是非常重要的"),new Course(91, 10, "https://www.runoob.com/hosting/hosting-tutorial.html", "【网站主机教程】", "如果您希望向全世界发布自己的网站，那么您的网站就需要被放置于一个 WEB 服务器"),new Course(92, 10, "https://www.runoob.com/tcpip/tcpip-tutorial.html", "【学习 TCP/IP】", "TCP/IP 是因特网的通信协议"),new Course(93, 10, "https://www.runoob.com/w3c/w3c-tutorial.html", "【学习 W3C】", "W3C 让每个人都能在互联网上分享资源"),new Course(94, 10, "https://www.runoob.com/quality/quality-tutorial.html", "【网站品质】", "学习如何创建高质量的web网站")};}}
}

Catalog类用于存放目录数据

using System.Collections.Generic;namespace LINQcsdn {public class Catalog {public int CatalogId { get; private set; }public int CourseId { get; private set; }public string CatalogUrl { get; private set; }public string CatalogName { get; private set; }public Catalog(int id, int cId, string url, string name) {CatalogId = id;CourseId = cId;CatalogUrl = url;CatalogName = name;}public Catalog() : this(0, 0, "", "") { }public override string ToString() {string result = "{";result += "\"catalog_id\": " + $"{CatalogId}" + ", ";result += "\"course_id\": " + $"{CourseId}" + ", ";result += "\"catalog_name\": " + $"\"{CatalogName}\"" + ", ";result += "\"catalog_url\": " + $"\"{CatalogUrl}\"";result += "}";return result;}public static List<Catalog> GetList() {return new List<Catalog>() {new Catalog(1, 1, "https://www.runoob.com/html/html-tutorial.html", "HTML 教程"),new Catalog(2, 1, "https://www.runoob.com/html/html-intro.html", "HTML 简介"),new Catalog(3, 1, "https://www.runoob.com/html/html-editors.html", "HTML 编辑器"),new Catalog(4, 1, "https://www.runoob.com/html/html-basic.html", "HTML 基础"),new Catalog(5, 1, "https://www.runoob.com/html/html-elements.html", "HTML 元素"),new Catalog(6, 1, "https://www.runoob.com/html/html-attributes.html", "HTML 属性"),new Catalog(7, 1, "https://www.runoob.com/html/html-headings.html", "HTML 标题"),new Catalog(8, 1, "https://www.runoob.com/html/html-paragraphs.html", "HTML 段落"),new Catalog(9, 1, "https://www.runoob.com/html/html-formatting.html", "HTML 文本格式化"),new Catalog(10, 1, "https://www.runoob.com/html/html-links.html", "HTML 链接"),new Catalog(11, 1, "https://www.runoob.com/html/html-head.html", "HTML 头部"),new Catalog(12, 1, "https://www.runoob.com/html/html-css.html", "HTML CSS"),new Catalog(13, 1, "https://www.runoob.com/html/html-images.html", "HTML 图像"),new Catalog(14, 1, "https://www.runoob.com/html/html-tables.html", "HTML 表格"),new Catalog(15, 1, "https://www.runoob.com/html/html-lists.html", "HTML 列表"),new Catalog(16, 1, "https://www.runoob.com/html/html-blocks.html", "HTML 区块"),new Catalog(17, 1, "https://www.runoob.com/html/html-layouts.html", "HTML 布局"),new Catalog(18, 1, "https://www.runoob.com/html/html-forms.html", "HTML 表单"),new Catalog(19, 1, "https://www.runoob.com/html/html-iframes.html", "HTML 框架"),new Catalog(20, 1, "https://www.runoob.com/html/html-colors.html", "HTML 颜色"),new Catalog(21, 1, "https://www.runoob.com/html/html-colornames.html", "HTML 颜色名"),new Catalog(22, 1, "https://www.runoob.com/html/html-colorvalues.html", "HTML 颜色值"),new Catalog(23, 1, "https://www.runoob.com/html/html-scripts.html", "HTML 脚本"),new Catalog(24, 1, "https://www.runoob.com/html/html-entities.html", "HTML 字符实体"),new Catalog(25, 1, "https://www.runoob.com/html/html-url.html", "HTML URL"),new Catalog(26, 1, "https://www.runoob.com/html/html-quicklist.html", "HTML 速查列表"),new Catalog(27, 1, "https://www.runoob.com/html/html-summary.html", "HTML 总结"),new Catalog(28, 1, "https://www.runoob.com/html/html-xhtml.html", "XHTML 简介"),new Catalog(29, 1, "https://www.runoob.com/html/html5-intro.html", "HTML5 教程"),new Catalog(30, 1, "https://www.runoob.comhtml5-browsers.html", "HTML5 浏览器支持"),new Catalog(31, 1, "https://www.runoob.com/html/html5-new-element.html", "HTML5 新元素"),new Catalog(32, 1, "https://www.runoob.com/html/html5-canvas.html", "HTML5 Canvas"),new Catalog(33, 1, "https://www.runoob.com/html/html5-svg.html", "HTML5 内联 SVG"),new Catalog(34, 1, "https://www.runoob.comhtml5-mathml.html", "HTML5 MathML"),new Catalog(35, 1, "https://www.runoob.com/html/html5-draganddrop.html", "HTML5 拖放"),new Catalog(36, 1, "https://www.runoob.com/html/html5-geolocation.html", "HTML5 地理定位"),new Catalog(37, 1, "https://www.runoob.com/html/html5-video.html", "HTML5 Video(视频)"),new Catalog(38, 1, "https://www.runoob.com/html/html5-audio.html", "HTML5 Audio(音频)"),new Catalog(39, 1, "https://www.runoob.com/html/html5-form-input-types.html", "HTML5 Input 类型"),new Catalog(40, 1, "https://www.runoob.com/html/html5-form-elements.html", "HTML5 表单元素"),new Catalog(41, 1, "https://www.runoob.com/html/html5-form-attributes.html", "HTML5 表单属性"),new Catalog(42, 1, "https://www.runoob.com/html/html5-semantic-elements.html", "HTML5 语义元素"),new Catalog(43, 1, "https://www.runoob.com/html/html5-webstorage.html", "HTML5 Web 存储"),new Catalog(44, 1, "https://www.runoob.comhtml5-web-sql.html", "HTML5 Web SQL"),new Catalog(45, 1, "https://www.runoob.com/html/html5-app-cache.html", "HTML5 应用程序缓存"),new Catalog(46, 1, "https://www.runoob.com/html/html5-webworkers.html", "HTML5 Web Workers"),new Catalog(47, 1, "https://www.runoob.com/html/html5-serversentevents.html", "HTML5 SSE"),new Catalog(48, 1, "https://www.runoob.com/html/html5-websocket.html", "HTML5 WebSocket"),new Catalog(49, 1, "https://www.runoob.com/quiz/html5-quiz.html", "HTML5 测验"),new Catalog(50, 1, "https://www.runoob.com/html/html5-syntax.html", "HTML(5) 代码规范"),new Catalog(51, 1, "https://www.runoob.com/html/html-media.html", "HTML 媒体(Media)"),new Catalog(52, 1, "https://www.runoob.com/html/html-object.html", "HTML 插件"),new Catalog(53, 1, "https://www.runoob.com/html/html-sounds.html", "HTML 音频(Audio)"),new Catalog(54, 1, "https://www.runoob.com/html/html-videos.html", "HTML 视频（Video）播放"),new Catalog(55, 1, "https://www.runoob.com/html/html-examples.html", "HTML 实例"),new Catalog(56, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-reference.html", "HTML 标签列表(字母排序)"),new Catalog(57, 1, "https://www.runoob.comhttp://www.runoob.com/tags/ref-byfunc.html", "HTML 标签列表（功能排序）"),new Catalog(58, 1, "https://www.runoob.comhttp://www.runoob.com/tags/ref-standardattributes.html", "HTML 属性"),new Catalog(59, 1, "https://www.runoob.comhttp://www.runoob.com/tags/ref-eventattributes.html", "HTML 事件"),new Catalog(60, 1, "https://www.runoob.comhttp://www.runoob.com/tags/ref-canvas.html", "HTML 画布"),new Catalog(61, 1, "https://www.runoob.comhttp://www.runoob.com/tags/ref-av-dom.html", "HTML 音频/视频"),new Catalog(62, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-elementsdoctypes.html", "HTML 有效DOCTYPES"),new Catalog(63, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-colorname.html", "HTML 颜色名"),new Catalog(64, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-colorpicker.html", "HTML 拾色器"),new Catalog(65, 1, "https://www.runoob.com/charsets/html-charsets.html", "HTML 字符集"),new Catalog(66, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-ascii.html", "HTML ASCII"),new Catalog(67, 1, "https://www.runoob.comhttp://www.runoob.com/tags/ref-entities.html", "HTML ISO-8859-1"),new Catalog(68, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-symbols.html", "HTML 符号"),new Catalog(69, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-urlencode.html", "HTML URL 编码"),new Catalog(70, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-language-codes.html", "HTML 语言代码"),new Catalog(71, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-httpmessages.html", "HTTP 消息"),new Catalog(72, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-httpmethods.html", "HTTP 方法"),new Catalog(73, 1, "https://www.runoob.comhttp://www.runoob.com/tags/html-keyboardshortcuts.html", "键盘快捷键"),new Catalog(74, 2, "https://www.runoob.com/html/html-tutorial.html", "HTML 教程"),new Catalog(75, 2, "https://www.runoob.com/html/html-intro.html", "HTML 简介"),new Catalog(76, 2, "https://www.runoob.com/html/html-editors.html", "HTML 编辑器"),new Catalog(77, 2, "https://www.runoob.com/html/html-basic.html", "HTML 基础"),new Catalog(78, 2, "https://www.runoob.com/html/html-elements.html", "HTML 元素"),new Catalog(79, 2, "https://www.runoob.com/html/html-attributes.html", "HTML 属性"),new Catalog(80, 2, "https://www.runoob.com/html/html-headings.html", "HTML 标题"),new Catalog(81, 2, "https://www.runoob.com/html/html-paragraphs.html", "HTML 段落"),new Catalog(82, 2, "https://www.runoob.com/html/html-formatting.html", "HTML 文本格式化"),new Catalog(83, 2, "https://www.runoob.com/html/html-links.html", "HTML 链接"),new Catalog(84, 2, "https://www.runoob.com/html/html-head.html", "HTML 头部"),new Catalog(85, 2, "https://www.runoob.com/html/html-css.html", "HTML CSS"),new Catalog(86, 2, "https://www.runoob.com/html/html-images.html", "HTML 图像"),new Catalog(87, 2, "https://www.runoob.com/html/html-tables.html", "HTML 表格"),new Catalog(88, 2, "https://www.runoob.com/html/html-lists.html", "HTML 列表"),new Catalog(89, 2, "https://www.runoob.com/html/html-blocks.html", "HTML 区块"),new Catalog(90, 2, "https://www.runoob.com/html/html-layouts.html", "HTML 布局"),new Catalog(91, 2, "https://www.runoob.com/html/html-forms.html", "HTML 表单"),new Catalog(92, 2, "https://www.runoob.com/html/html-iframes.html", "HTML 框架"),new Catalog(93, 2, "https://www.runoob.com/html/html-colors.html", "HTML 颜色"),new Catalog(94, 2, "https://www.runoob.com/html/html-colornames.html", "HTML 颜色名"),new Catalog(95, 2, "https://www.runoob.com/html/html-colorvalues.html", "HTML 颜色值"),new Catalog(96, 2, "https://www.runoob.com/html/html-scripts.html", "HTML 脚本"),new Catalog(97, 2, "https://www.runoob.com/html/html-entities.html", "HTML 字符实体"),new Catalog(98, 2, "https://www.runoob.com/html/html-url.html", "HTML URL"),new Catalog(99, 2, "https://www.runoob.com/html/html-quicklist.html", "HTML 速查列表"),new Catalog(100, 2, "https://www.runoob.com/html/html-summary.html", "HTML 总结"),// ...// ...// ...new Catalog(2749, 91, "https://www.runoob.comhttps://www.runoob.com/linux/linux-cloud-server.html", "云服务器"),new Catalog(2750, 92, "https://www.runoob.com/tcpip/tcpip-tutorial.html", "TCP/IP 教程"),new Catalog(2751, 92, "https://www.runoob.com/tcpip/tcpip-intro.html", "TCP/IP 介绍"),new Catalog(2752, 92, "https://www.runoob.com/tcpip/tcpip-addressing.html", "TCP/IP 寻址"),new Catalog(2753, 92, "https://www.runoob.com/tcpip/tcpip-protocols.html", "TCP/IP 协议"),new Catalog(2754, 92, "https://www.runoob.com/tcpip/tcpip-email.html", "TCP/IP 邮件"),new Catalog(2755, 93, "https://www.runoob.com/w3c/w3c-tutorial.html", "W3C 教程"),new Catalog(2756, 93, "https://www.runoob.com/w3c/w3c-intro.html", "W3C 简介"),new Catalog(2757, 93, "https://www.runoob.com/w3c/w3c-process.html", "W3C 程序"),new Catalog(2758, 93, "https://www.runoob.com/w3c/w3c-html.html", "W3C HTML 活动"),new Catalog(2759, 93, "https://www.runoob.com/w3c/w3c-xhtml.html", "W3C XHTML 活动"),new Catalog(2760, 93, "https://www.runoob.com/w3c/w3c-xml.html", "W3C XML 活动"),new Catalog(2761, 93, "https://www.runoob.com/w3c/w3c-css.html", "W3C CSS 活动"),new Catalog(2762, 93, "https://www.runoob.com/w3c/w3c-xsl.html", "W3C XSL 活动"),new Catalog(2763, 93, "https://www.runoob.com/w3c/w3c-schema.html", "W3C XML Schema 活动"),new Catalog(2764, 93, "https://www.runoob.com/w3c/w3c-xpath.html", "W3C XPath 活动"),new Catalog(2765, 93, "https://www.runoob.com/w3c/w3c-xquery.html", "W3C XQuery 活动"),new Catalog(2766, 93, "https://www.runoob.com/w3c/w3c-dom.html", "W3C DOM 活动"),new Catalog(2767, 93, "https://www.runoob.com/w3c/w3c-soap.html", "W3C SOAP 活动"),new Catalog(2768, 93, "https://www.runoob.com/w3c/w3c-wsdl.html", "W3C WSDL 活动"),new Catalog(2769, 93, "https://www.runoob.com/w3c/w3c-rdf.html", "W3C RDF 活动"),new Catalog(2770, 93, "https://www.runoob.com/w3c/w3c-other.html", "其他 W3C 活动"),new Catalog(2771, 94, "https://www.runoob.com/quality/quality-tutorial.html", "网站品质教程"),new Catalog(2772, 94, "https://www.runoob.com/quality/quality-standards.html", "Web 品质标准"),new Catalog(2773, 94, "https://www.runoob.com/quality/quality-elements.html", "Web 品质 - 重要的HTML元素"),new Catalog(2774, 94, "https://www.runoob.com/quality/quality-styles.html", "Web 品质样式表"),new Catalog(2775, 94, "https://www.runoob.com/quality/quality-readability.html", "Web 品质可读性"),new Catalog(2776, 94, "https://www.runoob.com/quality/quality-accessibility.html", "Web 无障碍(WAI)"),new Catalog(2777, 94, "https://www.runoob.com/quality/quality-international.html", "Web 品质国际化")};}}
}

小结

这一篇文章主要是创建一些数据
下一篇才是重点
由于数据太多中间省略了两千多条数据

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