C# Linq排序

今天在家看了一下linq，實踐了一下書中代碼，發現排序和查重的先後順序太重要了。

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 
 namespace LinqLearning
 {
     class Program
     {
         private static int[] GenerateLotsOfNumbers(int count)
         {
             Random generator = new Random(0);
             int[] result = new int[count];
             for (int i = 0; i < count; i++)
             {
                 result[i] = generator.Next();
             }
             return result;
         }
 
         static void Main(string[] args)
         {
             int[] numbers = GenerateLotsOfNumbers(12345678);
 
             var queryResults = from n in numbers
                                where n < 1000
                                orderby n descending
                                select n;
             Console.WriteLine("查詢語法排序結果：");
             DateTime start = DateTime.Now;
             foreach (var item in queryResults)
                 Console.WriteLine(item);
             Console.WriteLine("消耗時間：{0}",DateTime.Now-start);
 
             var queryResult = numbers.OrderByDescending(n => n).Where(n => n < 1000);
             Console.WriteLine("方法排序結果（排序字段在前）：");
             start = DateTime.Now;
             foreach (var item in queryResult)
                 Console.WriteLine(item);
             Console.WriteLine("消耗時間：{0}", DateTime.Now - start);
 
             var query = numbers.Where(n => n < 1000).OrderByDescending(n => n);
             Console.WriteLine("方法排序結果（排序字段在後）：");
             start = DateTime.Now;
             foreach (var item in query)
                 Console.WriteLine(item);
             Console.WriteLine("消耗時間：{0}", DateTime.Now - start);
 
             Console.ReadKey();
         }
     }
 }