C# Linq基本常用用法

1.什么是Linq？

　　Lanaguage Interated Query（语言集成查询），Linq 是集成C# 和VB这些语言中用于提供数据查询能力的一个新特性。

　　这里只介绍两种基本常用用法。

　　学习方法参考示例代码

1） where  查询

 class Program

    {

        static void Main(string[] args)

        {

            int[] nums = new int[] { , , , , , , , , ,  };

            var result = from m in nums where m >=  select m;

            foreach (var v in result)

            {

                Console.WriteLine("v:" + v + "  ");

            }

            Console.WriteLine("\n");

            //使用Lambda 表达式进行Linq查询

            var result2 = nums.Where(m => m >= );

            foreach (var v in result2)

            {

                Console.WriteLine("v2:" + v + "  ");

            }

            List<People> mans = new List<People>();

            mans.Add(new People { id = , sex = true, name = "小王", birthday = Convert.ToDateTime("1994-1-1") });

            mans.Add(new People { id = , sex = false, name = "小张", birthday = Convert.ToDateTime("1954-1-1") });

            mans.Add(new People { id = , sex = true, name = "小明", birthday = Convert.ToDateTime("1993-1-1") });

            mans.Add(new People { id = , sex = false, name = "小红", birthday = Convert.ToDateTime("1974-1-1") });

            var resultMan = from man in mans where man.id <  && man.sex select man;

            foreach (var v in resultMan)

            {

                Console.WriteLine("v:"+v.id + " name :"+v.name);

            }

            Console.Read();

        }

    }

    class People

    {

        public string name { get; set; }

        public int id { get; set; }

        public bool sex { get; set; }

        public DateTime birthday { get; set; }

        public int GetAge()

        {

            return DateTime.Now.Year - birthday.Year;

        }

    }

2) order 排序

descending 降序

ascending 升序

   List<int> numbers = new List<int>() { , , , , , ,  };

             var resultNums = from m in numbers orderby m  select m;

             foreach (var v in resultNums)

             {

                 Console.WriteLine("v num:"+v);

             }

             Console.WriteLine("\n");

             var resultNums2 = from m in numbers orderby m descending select m;

             foreach (var v in resultNums2)

             {

                 Console.WriteLine("v2 num:" + v);

             }

             Console.WriteLine("\n");

             var resultNums3 = from m in numbers orderby m ascending select m;

             foreach (var v in resultNums3)

             {

                 Console.WriteLine("v3 num:" + v);

             }

2.优点

　　1.简单，容易上手，极大节省开发效率。

　　 2.很大程度上节省代码量。

建议：Unity开发的话，一般都不要去使用，会产生GC。

参考链接：http://www.cnblogs.com/jara/p/3472215.html  http://www.cnblogs.com/hgmyz/p/7068150.html

C# Linq基本常用用法的相关教程结束。