ArrayList.Remove メソッド

.NET Framework クラス ライブラリ リファレンス

ArrayList.Remove メソッド

ArrayList 内で最初に見つかった特定のオブジェクトを削除します。

名前空間: System.Collections
アセンブリ: mscorlib (mscorlib.dll 内)
構文

Visual Basic (宣言)

Public Overridable Sub Remove
 ( _
    obj As Object _
)

Visual Basic (使用法)

Dim instance As ArrayList
Dim obj As Object

instance.Remove(obj)

C#

public virtual void Remove (
    Object obj
)

C++

public:
virtual void Remove (
    Object^ obj
)

J#

public void Remove (
    Object obj
)

JScript

public function Remove (
    obj : Object
)

パラメータ

obj

ArrayList から削除する Object。値は null 参照 (Visual Basic では Nothing) に設定できます。

例外

例外の種類	条件
NotSupportedException	ArrayList は読み取り専用です。 または ArrayList が固定サイズです。

解説

ArrayList に指定されたオブジェクトが含まれていない場合、ArrayList は変更されません。例外はスローされません。

このメソッドは順次検索を実行します。したがって、このメソッドは、O(n) 操作です。ここで、n は Count です。

このメソッドは、Object.Equals を呼び出して、等しいかどうかを判断します。

リストなどの連続する要素のコレクションでは、空白になった位置を埋めるために、削除された要素の後にある要素の位置が繰り上げられます。インデックス付きのコレクションの場合は、移動した要素のインデックスも更新されます。この動作は、要素が概念的にバケットにグループ化されているハッシュ テーブルなどのコレクションには適用されません。

使用例

ArrayList から要素を削除する方法を次のコード例に示します。

Visual Basic

Imports System
Imports System.Collections
Imports Microsoft.VisualBasic

Public Class SamplesArrayList    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a new ArrayList.
        Dim myAL As New
 ArrayList()
        myAL.Add("The")
        myAL.Add("quick")
        myAL.Add("brown")
        myAL.Add("fox")
        myAL.Add("jumped")
        myAL.Add("over")
        myAL.Add("the")
        myAL.Add("lazy")
        myAL.Add("dog")
        
        ' Displays the ArrayList.
        Console.WriteLine("The ArrayList initially contains the
 following:")
        PrintValues(myAL)
        
        ' Removes the element containing "lazy".
        myAL.Remove("lazy")
        
        ' Displays the current state of the ArrayList.
        Console.WriteLine("After removing ""lazy"":")
        PrintValues(myAL)
        
        ' Removes the element at index 5.
        myAL.RemoveAt(5)
        
        ' Displays the current state of the ArrayList.
        Console.WriteLine("After removing the element at index
 5:")
        PrintValues(myAL)
        
        ' Removes three elements starting at index 4.
        myAL.RemoveRange(4, 3)
        
        ' Displays the current state of the ArrayList.
        Console.WriteLine("After removing three elements starting
 at index 4:")
        PrintValues(myAL)
    End Sub
    
    Public Shared Sub PrintValues(myList
 As IEnumerable)
        Dim obj As [Object]
        For Each obj In
  myList
            Console.Write("   {0}", obj)
        Next obj
        Console.WriteLine()
    End Sub 'PrintValues

End Class


' This code produces the following output.
' 
' The ArrayList initially contains the following:
'    The   quick   brown   fox   jumped   over   the   lazy   dog
' After removing "lazy":
'    The   quick   brown   fox   jumped   over   the   dog
' After removing the element at index 5:
'    The   quick   brown   fox   jumped   the   dog
' After removing three elements starting at index 4:
'    The   quick   brown   fox

C#

using System;
using System.Collections;
public class SamplesArrayList  {

   public static void Main()
  {

      // Creates and initializes a new ArrayList.
      ArrayList myAL = new ArrayList();
      myAL.Add( "The" );
      myAL.Add( "quick" );
      myAL.Add( "brown" );
      myAL.Add( "fox" );
      myAL.Add( "jumped" );
      myAL.Add( "over" );
      myAL.Add( "the" );
      myAL.Add( "lazy" );
      myAL.Add( "dog" );

      // Displays the ArrayList.
      Console.WriteLine( "The ArrayList initially contains the following:"
 );
      PrintValues( myAL );

      // Removes the element containing "lazy".
      myAL.Remove( "lazy" );

      // Displays the current state of the ArrayList.
      Console.WriteLine( "After removing \"lazy\":" );
      PrintValues( myAL );

      // Removes the element at index 5.
      myAL.RemoveAt( 5 );

      // Displays the current state of the ArrayList.
      Console.WriteLine( "After removing the element at index 5:" );
      PrintValues( myAL );

      // Removes three elements starting at index 4.
      myAL.RemoveRange( 4, 3 );

      // Displays the current state of the ArrayList.
      Console.WriteLine( "After removing three elements starting at index 4:"
 );
      PrintValues( myAL );
   }

   public static void PrintValues(
 IEnumerable myList )  {
      foreach ( Object obj in myList )
         Console.Write( "   {0}", obj );
      Console.WriteLine();
   }

}
/* 
This code produces the following output.

The ArrayList initially contains the following:
   The   quick   brown   fox   jumped   over   the   lazy   dog
After removing "lazy":
   The   quick   brown   fox   jumped   over   the   dog
After removing the element at index 5:
   The   quick   brown   fox   jumped   the   dog
After removing three elements starting at index 4:
   The   quick   brown   fox
*/ 

C++

using namespace System;
using namespace System::Collections;
void PrintValues( IEnumerable^ myList );
int main()
{
   
   // Creates and initializes a new ArrayList.
   ArrayList^ myAL = gcnew ArrayList;
   myAL->Add( "The" );
   myAL->Add( "quick" );
   myAL->Add( "brown" );
   myAL->Add( "fox" );
   myAL->Add( "jumped" );
   myAL->Add( "over" );
   myAL->Add( "the" );
   myAL->Add( "lazy" );
   myAL->Add( "dog" );
   
   // Displays the ArrayList.
   Console::WriteLine( "The ArrayList initially contains the following:"
 );
   PrintValues( myAL );
   
   // Removes the element containing "lazy".
   myAL->Remove( "lazy" );
   
   // Displays the current state of the ArrayList.
   Console::WriteLine( "After removing \"lazy\":" );
   PrintValues( myAL );
   
   // Removes the element at index 5.
   myAL->RemoveAt( 5 );
   
   // Displays the current state of the ArrayList.
   Console::WriteLine( "After removing the element at index 5:" );
   PrintValues( myAL );
   
   // Removes three elements starting at index 4.
   myAL->RemoveRange( 4, 3 );
   
   // Displays the current state of the ArrayList.
   Console::WriteLine( "After removing three elements starting at index 4:"
 );
   PrintValues( myAL );
}

void PrintValues( IEnumerable^ myList )
{
   IEnumerator^ myEnum = myList->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::Write( "   {0}", obj );
   }

   Console::WriteLine();
}

/* 
 This code produces the following output.
 
 The ArrayList initially contains the following:
    The   quick   brown   fox   jumped   over   the   lazy   dog
 After removing "lazy":
    The   quick   brown   fox   jumped   over   the   dog
 After removing the element at index 5:
    The   quick   brown   fox   jumped   the   dog
 After removing three elements starting at index 4:
    The   quick   brown   fox
 */

J#

import System.*;
import System.Collections.*;

public class SamplesArrayList
{
    public static void main(String[]
 args)
    {
        // Creates and initializes a new ArrayList.
        ArrayList myAL = new ArrayList();

        myAL.Add("The");
        myAL.Add("quick");
        myAL.Add("brown");
        myAL.Add("fox");
        myAL.Add("jumped");
        myAL.Add("over");
        myAL.Add("the");
        myAL.Add("lazy");
        myAL.Add("dog");

        // Displays the ArrayList.
        Console.WriteLine("The ArrayList initially contains the following:");
        PrintValues(myAL);

        // Removes the element containing "lazy".
        myAL.Remove("lazy");

        // Displays the current state of the ArrayList.
        Console.WriteLine("After removing \"lazy\":");
        PrintValues(myAL);

        // Removes the element at index 5.
        myAL.RemoveAt(5);

        // Displays the current state of the ArrayList.
        Console.WriteLine("After removing the element at index 5:");
        PrintValues(myAL);

        // Removes three elements starting at index 4.
        myAL.RemoveRange(4, 3);

        // Displays the current state of the ArrayList.
        Console.WriteLine("After removing three elements starting at index 4:");
        PrintValues(myAL);
    } //main

    public static void PrintValues(IEnumerable
 myList)
    {
        IEnumerator objMyEnum = myList.GetEnumerator();
        while (objMyEnum.MoveNext()) {
            Object obj = objMyEnum.get_Current();
            Console.Write("   {0}", obj);
        }
        Console.WriteLine();
    } //PrintValues
} //SamplesArrayList 
/* 
 This code produces the following output.
 
 The ArrayList initially contains the following:
    The   quick   brown   fox   jumped   over   the   lazy   dog
 After removing "lazy":
    The   quick   brown   fox   jumped   over   the   dog
 After removing the element at index 5:
    The   quick   brown   fox   jumped   the   dog
 After removing three elements starting at index 4:
    The   quick   brown   fox
 */

JScript

import System;
import System.Collections;

// Creates and initializes a new ArrayList.
var myAL : ArrayList = new ArrayList();
myAL.Add( "The" );
myAL.Add( "quick" );
myAL.Add( "brown" );
myAL.Add( "fox" );
myAL.Add( "jumped" );
myAL.Add( "over" );
myAL.Add( "the" );
myAL.Add( "lazy" );
myAL.Add( "dog" );

// Displays the ArrayList.
Console.WriteLine( "The ArrayList initially contains the following:" );
PrintValues( myAL );

// Removes the element containing "lazy".
myAL.Remove( "lazy" );

// Displays the current state of the ArrayList.
Console.WriteLine( "After removing \"lazy\":" );
PrintValues( myAL );

// Removes the element at index 5.
myAL.RemoveAt( 5 );

// Displays the current state of the ArrayList.
Console.WriteLine( "After removing the element at index 5:" );
PrintValues( myAL );

// Removes three elements starting at index 4.
myAL.RemoveRange( 4, 3 );

// Displays the current state of the ArrayList.
Console.WriteLine( "After removing three elements starting at index 4:"
 );
PrintValues( myAL );

function PrintValues( myList : IEnumerable )  {
   var myEnumerator : System.Collections.IEnumerator  = myList.GetEnumerator();
   while ( myEnumerator.MoveNext() )
      Console.Write( "\t{0}", myEnumerator.Current );
   Console.WriteLine();
}
 /* 
 This code produces the following output.
 
 The ArrayList initially contains the following:
     The    quick    brown    fox    jumped    over    the    lazy    dog
 After removing "lazy":
     The    quick    brown    fox    jumped    over    the    dog
 After removing the element at index 5:
     The    quick    brown    fox    jumped    the    dog
 After removing three elements starting at index 4:
     The    quick    brown    fox
 */ 

プラットフォーム

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。

バージョン情報

.NET Framework
サポート対象 : 2.0、1.1、1.0
.NET Compact Framework
サポート対象 : 2.0、1.0

参照

関連項目
ArrayList クラス
ArrayList メンバ
System.Collections 名前空間
RemoveAt
RemoveRange
Add
Insert
その他の技術情報
カルチャを認識しないコレクションの操作の実行