排序運算符

排序操作允許基於一個序列中的元素上的單個或多個屬性排序。

操作符	描述	C#查詢表達式語法	VB查詢表達式語法
OrderBy	按升序操作排序值	orderby	Order By
OrderByDescending	降序排序操作值	orderby ... descending	Order By ... Descending
ThenBy	執行二次排序按升序	orderby …, …	Order By …, …
ThenByDescending	執行二次排序以降序	orderby …, … descending	Order By …, … Descending
Reverse	進行反轉的元素的順序的集合	不適用	不適用

OrderBy, OrderByDescending例子 - 查詢表達式

C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Operators
{
  class Program
  {
     static void Main(string[] args)
     {
        int[] num = { -20, 12, 6, 10, 0, -3, 1 };
        //create a query that obtain the values in sorted order
        var posNums = from n in num
                      orderby n
                      select n;
        Console.Write("Values in ascending order: ");
     
        // Execute the query and display the results.
        foreach (int i in posNums) 
           Console.Write(i + " \n");

           var posNumsDesc = from n in num
                             orderby n descending
                             select n;
           Console.Write("\nValues in descending order: ");

        // Execute the query and display the results.
        foreach (int i in posNumsDesc) 
           Console.Write(i + " \n");

           Console.ReadLine();
     }
  }
}

VB

Module Module1
  Sub Main()
     Dim num As Integer() = {-20, 12, 6, 10, 0, -3, 1}

     Dim posNums = From n In num
                   Order By n
                   Select n
        Console.Write("Values in ascending order: ")

     For Each n In posNums
        Console.WriteLine(n)
     Next
 
     Dim posNumsDesc = From n In num
                       Order By n Descending
                       Select n
        Console.Write("Values in descending order: ")

     For Each n In posNumsDesc
        Console.WriteLine(n)
     Next
        Console.ReadLine()
  End Sub
End Module

當在C＃或VB上麵的代碼被編譯和執行時，它產生以下結果：

Values in ascending order: -20 
-3 
0 
1 
6 
10 
12
Values in descending order: 12 
10 
6 
1 
0 
-3 
-20

在Tenby和ThenbyDescending運算符，同樣的語法可以應用排序，順序將取決於列位置。第一列為優先。