Linq-filtering-operators

LINQでの演算子のフィルタリング

フィルタリングは、特定の条件を満たす選択された要素のみを持つように結果セットを制限する操作です。

Operator	Description	C# Query Expression Syntax	VB Query Expression Syntax
Where	Filter values based on a predicate function	where	Where
OfType	Filter values based on their ability to be as a specified type	Not Applicable	Not Applicable

Whereの例-クエリ式

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

C＃またはVBの上記のコードがコンパイルされて実行されると、次の結果が生成されます-

set