1.牛刀小试

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace linq{    class Program    {        static void Main(string[] args)        {            string[] words = { "hello","linq","good","wonderful"};            var shortWords = from word in words                             where word.Length <= 5                             select word;            foreach (var word in shortWords)            {                Console.WriteLine(word);            }            Console.ReadKey();        }    }}

2.Group分组处理

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace linq{    class Program    {        static void Main(string[] args)        {            string[] words = { "hello","linq","good","wonderful","world","beautiful"};            //VAR 是3.5新出的一个定义变量的类型，其实也就是弱化类型的定义。VAR可代替任何类型，编译器会根据上下文来判断你到底是想用什么类型的。            var groups = from word in words                         orderby word ascending                         group word by word.Length into lengthGroups                         orderby lengthGroups.Key descending                         select new { Length = lengthGroups.Key, Words = lengthGroups }; // 按长度将单词分组                                                        foreach (var group in groups)            {                Console.WriteLine("Words of length" + group.Length);                foreach (string word in group.Words)                {                    Console.WriteLine(" " + word);                }            }            Console.ReadKey();        }    }}

3.XML 案例

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Xml;using System.Xml.Linq;using System.Threading.Tasks;namespace linq{    class Book    {        public string Publisher;        public string Title;        public int Year;        public Book(string title,string publisher,int year)        {            Title = title;            Publisher = publisher;            Year = year;        }    }    class Program    {        static void Main(string[] args)        {            Book[] books = new Book[]            {                new Book("Ajax","Zhang",2015),                new Book("Java","Li",2016),                new Book(".Net","Zhao",2016),            };            XElement xml = new XElement("books",                from book in books                where book.Year == 2016                select new XElement("book",                    new XAttribute("title",book.Title),                    new XElement("publisher",book.Publisher)                    )            );            Console.WriteLine(xml);            Console.ReadKey();        }    }}本文转自TBHacker博客园博客，原文链接：http://www.cnblogs.com/jiqing9006/p/6909661.html，如需转载请自行联系原作者