LINQ 中的筛选运算符

筛选是一种限制结果集的操作，以便其仅包含满足特定条件的选定元素。

Where 示例 - 查询表达式

C#

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

namespace Operators {
   class Program {
      static void Main(string[] args) {

         string[] words = { "humpty", "dumpty","set", "on", "a", "wall" };

         IEnumerable<string> query = from word in words where word.Length == 3 select word;
		 
         foreach (string str in query)
            Console.WriteLine(str);
            Console.ReadLine();            
      }
   }
}

VB

Module Module1

   Sub Main()
      Dim words As String() = {"humpty", "dumpty", "set", "on", "a", "wall"}

      Dim query = From word In words Where word.Length = 3 Select word

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

当以 C# 或 VB 编译并执行上述代码时，它会生成以下结果 −

set