ArrayList.LastIndexOf メソッド

リファレンス

定義

名前空間:: System.Collections

アセンブリ:: mscorlib.dll, System.Collections.NonGeneric.dll

アセンブリ:: System.Runtime.dll

アセンブリ:: System.Collections.NonGeneric.dll

アセンブリ:: System.Runtime.Extensions.dll

アセンブリ:: mscorlib.dll

アセンブリ:: netstandard.dll

重要

一部の情報は、リリース前に大きく変更される可能性があるプレリリースされた製品に関するものです。 Microsoft は、ここに記載されている情報について、明示または黙示を問わず、一切保証しません。

ArrayList 全体またはその一部において、最後に値が出現した位置のインデックス番号 (0 から始まる) を返します。

オーバーロード

LastIndexOf(Object)	指定した Object を検索し、ArrayList 全体で最後に見つかった位置の 0 から始まるインデックスを返します。
LastIndexOf(Object, Int32)	指定した Object を検索し、最初の要素から、指定したインデックスまでの ArrayList 内の要素の範囲内で最後に出現する位置の 0 から始まるインデックス番号を返します。
LastIndexOf(Object, Int32, Int32)	指定した Object を検索し、指定した数の要素を含み、かつ指定したインデックスで終了する ArrayList 内の要素の範囲内で最後に出現する位置の 0 から始まるインデックス番号を返します。

LastIndexOf(Object)

Source:: ArrayList.cs

Source:: ArrayList.cs

Source:: ArrayList.cs

指定した Object を検索し、ArrayList 全体で最後に見つかった位置の 0 から始まるインデックスを返します。

public:
 virtual int LastIndexOf(System::Object ^ value);

public virtual int LastIndexOf (object value);

public virtual int LastIndexOf (object? value);

abstract member LastIndexOf : obj -> int
override this.LastIndexOf : obj -> int

Public Overridable Function LastIndexOf (value As Object) As Integer

パラメーター

value: Object

ArrayList 内で検索される Object。値として null を指定できます。

戻り値

Int32

value が見つかった場合は、ArrayList 全体で最後に見つかった位置のインデックス番号 (0 から始まる)。それ以外の場合は -1。

例

次のコード例は、指定した要素の最後に出現するインデックスを決定する方法を示しています。

using namespace System;
using namespace System::Collections;
void PrintIndexAndValues( IEnumerable^ myList );
int main()
{
   
   // Creates and initializes a new ArrayList with three elements of the same value.
   ArrayList^ myAL = gcnew ArrayList;
   myAL->Add( "the" );
   myAL->Add( "quick" );
   myAL->Add( "brown" );
   myAL->Add( "fox" );
   myAL->Add( "jumps" );
   myAL->Add( "over" );
   myAL->Add( "the" );
   myAL->Add( "lazy" );
   myAL->Add( "dog" );
   myAL->Add( "in" );
   myAL->Add( "the" );
   myAL->Add( "barn" );
   
   // Displays the values of the ArrayList.
   Console::WriteLine( "The ArrayList contains the following values:" );
   PrintIndexAndValues( myAL );
   
   // Searches for the last occurrence of the duplicated value.
   String^ myString = "the";
   int myIndex = myAL->LastIndexOf( myString );
   Console::WriteLine( "The last occurrence of \"{0}\" is at index {1}.", myString, myIndex );
   
   // Searches for the last occurrence of the duplicated value in the first section of the ArrayList.
   myIndex = myAL->LastIndexOf( myString, 8 );
   Console::WriteLine( "The last occurrence of \"{0}\" between the start and index 8 is at index {1}.", myString, myIndex );
   
   // Searches for the last occurrence of the duplicated value in a section of the ArrayList.  Note that the start index is greater than the end index because the search is done backward.
   myIndex = myAL->LastIndexOf( myString, 10, 6 );
   Console::WriteLine( "The last occurrence of \"{0}\" between index 10 and index 5 is at index {1}.", myString, myIndex );
}

void PrintIndexAndValues( IEnumerable^ myList )
{
   int i = 0;
   IEnumerator^ myEnum = myList->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::WriteLine( "   [{0}]:    {1}", i++, obj );
   }

   Console::WriteLine();
}

/*
 This code produces the following output.
 
 The ArrayList contains the following values:
    [0]:    the
    [1]:    quick
    [2]:    brown
    [3]:    fox
    [4]:    jumps
    [5]:    over
    [6]:    the
    [7]:    lazy
    [8]:    dog
    [9]:    in
    [10]:    the
    [11]:    barn

 The last occurrence of "the" is at index 10.
 The last occurrence of "the" between the start and index 8 is at index 6.
 The last occurrence of "the" between index 10 and index 5 is at index 10.
 */

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

   public static void Main()  {

      // Creates and initializes a new ArrayList with three elements of the same value.
      ArrayList myAL = new ArrayList();
      myAL.Add( "the" );
      myAL.Add( "quick" );
      myAL.Add( "brown" );
      myAL.Add( "fox" );
      myAL.Add( "jumps" );
      myAL.Add( "over" );
      myAL.Add( "the" );
      myAL.Add( "lazy" );
      myAL.Add( "dog" );
      myAL.Add( "in" );
      myAL.Add( "the" );
      myAL.Add( "barn" );

      // Displays the values of the ArrayList.
      Console.WriteLine( "The ArrayList contains the following values:" );
      PrintIndexAndValues( myAL );

      // Searches for the last occurrence of the duplicated value.
      string myString = "the";
      int myIndex = myAL.LastIndexOf( myString );
      Console.WriteLine( "The last occurrence of \"{0}\" is at index {1}.", myString, myIndex );

      // Searches for the last occurrence of the duplicated value in the first section of the ArrayList.
      myIndex = myAL.LastIndexOf( myString, 8 );
      Console.WriteLine( "The last occurrence of \"{0}\" between the start and index 8 is at index {1}.", myString, myIndex );

      // Searches for the last occurrence of the duplicated value in a section of the ArrayList.  Note that the start index is greater than the end index because the search is done backward.
      myIndex = myAL.LastIndexOf( myString, 10, 6 );
      Console.WriteLine( "The last occurrence of \"{0}\" between index 10 and index 5 is at index {1}.", myString, myIndex );
   }

   public static void PrintIndexAndValues( IEnumerable myList )  {
      int i = 0;
      foreach ( Object obj in myList )
         Console.WriteLine( "   [{0}]:    {1}", i++, obj );
      Console.WriteLine();
   }
}


/*
This code produces the following output.

The ArrayList contains the following values:
   [0]:    the
   [1]:    quick
   [2]:    brown
   [3]:    fox
   [4]:    jumps
   [5]:    over
   [6]:    the
   [7]:    lazy
   [8]:    dog
   [9]:    in
   [10]:    the
   [11]:    barn

The last occurrence of "the" is at index 10.
The last occurrence of "the" between the start and index 8 is at index 6.
The last occurrence of "the" between index 10 and index 5 is at index 10.
*/

Imports System.Collections

Public Class SamplesArrayList
   
   Public Shared Sub Main()
      
      ' Creates and initializes a new ArrayList with three elements of the same value.
      Dim myAL As New ArrayList()
      myAL.Add("the")
      myAL.Add("quick")
      myAL.Add("brown")
      myAL.Add("fox")
      myAL.Add("jumps")
      myAL.Add("over")
      myAL.Add("the")
      myAL.Add("lazy")
      myAL.Add("dog")
      myAL.Add("in")
      myAL.Add("the")
      myAL.Add("barn")
      
      ' Displays the values of the ArrayList.
      Console.WriteLine("The ArrayList contains the following values:")
      PrintIndexAndValues(myAL)
      
      ' Searches for the last occurrence of the duplicated value.
      Dim myString As [String] = "the"
      Dim myIndex As Integer = myAL.LastIndexOf(myString)
      Console.WriteLine("The last occurrence of ""{0}"" is at index {1}.", myString, myIndex)
      
      ' Searches for the last occurrence of the duplicated value in the first section of the ArrayList.
      myIndex = myAL.LastIndexOf(myString, 8)
      Console.WriteLine("The last occurrence of ""{0}"" between the start and index 8 is at index {1}.", myString, myIndex)
      
      ' Searches for the last occurrence of the duplicated value in a section of the ArrayList.  Note that the start index is greater than the end index because the search is done backward.
      myIndex = myAL.LastIndexOf(myString, 10, 6)
      Console.WriteLine("The last occurrence of ""{0}"" between index 10 and index 5 is at index {1}.", myString, myIndex)
   End Sub
   
   
   Public Shared Sub PrintIndexAndValues(myList As IEnumerable)
      Dim i as Integer
      Dim obj As [Object]
      For Each obj In  myList
         Console.WriteLine("   [{0}]:    {1}", i, obj)
         i = i + 1
      Next obj
      Console.WriteLine()
   End Sub

End Class

' This code produces the following output.
'
' The ArrayList contains the following values:
'    [0]:    the
'    [1]:    quick
'    [2]:    brown
'    [3]:    fox
'    [4]:    jumps
'    [5]:    over
'    [6]:    the
'    [7]:    lazy
'    [8]:    dog
'    [9]:    in
'    [10]:    the
'    [11]:    barn
'
' The last occurrence of "the" is at index 10.
' The last occurrence of "the" between the start and index 8 is at index 6.
' The last occurrence of "the" between index 10 and index 5 is at index 10.

注釈

は ArrayList 、最後の要素から始まり、最初の要素で終わる後方に検索されます。

このメソッドは線形検索を実行します。したがって、このメソッドは操作であり O(n) 、は nCountです。

.NET Framework 2.0 以降では、このメソッドはコレクションのオブジェクト Equals と CompareTo メソッドをitem使用して、項目が存在するかどうかを判断します。以前のバージョンの.NET Frameworkでは、この決定は、コレクション内のオブジェクトでパラメーターの item メソッドと CompareTo メソッドを使用Equalsして行われました。

こちらもご覧ください

適用対象

LastIndexOf(Object, Int32)

Source:: ArrayList.cs

Source:: ArrayList.cs

Source:: ArrayList.cs

指定した Object を検索し、最初の要素から、指定したインデックスまでの ArrayList 内の要素の範囲内で最後に出現する位置の 0 から始まるインデックス番号を返します。

public:
 virtual int LastIndexOf(System::Object ^ value, int startIndex);

public virtual int LastIndexOf (object value, int startIndex);

public virtual int LastIndexOf (object? value, int startIndex);

abstract member LastIndexOf : obj * int -> int
override this.LastIndexOf : obj * int -> int

Public Overridable Function LastIndexOf (value As Object, startIndex As Integer) As Integer

パラメーター

value: Object

ArrayList 内で検索される Object。値として null を指定できます。

startIndex: Int32

後方検索の開始位置を示す 0 から始まるインデックス。

戻り値

Int32

最初の要素から startIndex までの ArrayList 内の要素の範囲内で value が見つかった場合は、最後に見つかった位置の 0 から始まるインデックス番号。それ以外の場合は -1。

例外

ArgumentOutOfRangeException

startIndex は ArrayListの有効なインデックスの範囲外です。

例

次のコード例は、指定した要素の最後に出現するインデックスを決定する方法を示しています。

using namespace System;
using namespace System::Collections;
void PrintIndexAndValues( IEnumerable^ myList );
int main()
{
   
   // Creates and initializes a new ArrayList with three elements of the same value.
   ArrayList^ myAL = gcnew ArrayList;
   myAL->Add( "the" );
   myAL->Add( "quick" );
   myAL->Add( "brown" );
   myAL->Add( "fox" );
   myAL->Add( "jumps" );
   myAL->Add( "over" );
   myAL->Add( "the" );
   myAL->Add( "lazy" );
   myAL->Add( "dog" );
   myAL->Add( "in" );
   myAL->Add( "the" );
   myAL->Add( "barn" );
   
   // Displays the values of the ArrayList.
   Console::WriteLine( "The ArrayList contains the following values:" );
   PrintIndexAndValues( myAL );
   
   // Searches for the last occurrence of the duplicated value.
   String^ myString = "the";
   int myIndex = myAL->LastIndexOf( myString );
   Console::WriteLine( "The last occurrence of \"{0}\" is at index {1}.", myString, myIndex );
   
   // Searches for the last occurrence of the duplicated value in the first section of the ArrayList.
   myIndex = myAL->LastIndexOf( myString, 8 );
   Console::WriteLine( "The last occurrence of \"{0}\" between the start and index 8 is at index {1}.", myString, myIndex );
   
   // Searches for the last occurrence of the duplicated value in a section of the ArrayList.  Note that the start index is greater than the end index because the search is done backward.
   myIndex = myAL->LastIndexOf( myString, 10, 6 );
   Console::WriteLine( "The last occurrence of \"{0}\" between index 10 and index 5 is at index {1}.", myString, myIndex );
}

void PrintIndexAndValues( IEnumerable^ myList )
{
   int i = 0;
   IEnumerator^ myEnum = myList->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::WriteLine( "   [{0}]:    {1}", i++, obj );
   }

   Console::WriteLine();
}

/*
 This code produces the following output.
 
 The ArrayList contains the following values:
    [0]:    the
    [1]:    quick
    [2]:    brown
    [3]:    fox
    [4]:    jumps
    [5]:    over
    [6]:    the
    [7]:    lazy
    [8]:    dog
    [9]:    in
    [10]:    the
    [11]:    barn

 The last occurrence of "the" is at index 10.
 The last occurrence of "the" between the start and index 8 is at index 6.
 The last occurrence of "the" between index 10 and index 5 is at index 10.
 */

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

   public static void Main()  {

      // Creates and initializes a new ArrayList with three elements of the same value.
      ArrayList myAL = new ArrayList();
      myAL.Add( "the" );
      myAL.Add( "quick" );
      myAL.Add( "brown" );
      myAL.Add( "fox" );
      myAL.Add( "jumps" );
      myAL.Add( "over" );
      myAL.Add( "the" );
      myAL.Add( "lazy" );
      myAL.Add( "dog" );
      myAL.Add( "in" );
      myAL.Add( "the" );
      myAL.Add( "barn" );

      // Displays the values of the ArrayList.
      Console.WriteLine( "The ArrayList contains the following values:" );
      PrintIndexAndValues( myAL );

      // Searches for the last occurrence of the duplicated value.
      string myString = "the";
      int myIndex = myAL.LastIndexOf( myString );
      Console.WriteLine( "The last occurrence of \"{0}\" is at index {1}.", myString, myIndex );

      // Searches for the last occurrence of the duplicated value in the first section of the ArrayList.
      myIndex = myAL.LastIndexOf( myString, 8 );
      Console.WriteLine( "The last occurrence of \"{0}\" between the start and index 8 is at index {1}.", myString, myIndex );

      // Searches for the last occurrence of the duplicated value in a section of the ArrayList.  Note that the start index is greater than the end index because the search is done backward.
      myIndex = myAL.LastIndexOf( myString, 10, 6 );
      Console.WriteLine( "The last occurrence of \"{0}\" between index 10 and index 5 is at index {1}.", myString, myIndex );
   }

   public static void PrintIndexAndValues( IEnumerable myList )  {
      int i = 0;
      foreach ( Object obj in myList )
         Console.WriteLine( "   [{0}]:    {1}", i++, obj );
      Console.WriteLine();
   }
}


/*
This code produces the following output.

The ArrayList contains the following values:
   [0]:    the
   [1]:    quick
   [2]:    brown
   [3]:    fox
   [4]:    jumps
   [5]:    over
   [6]:    the
   [7]:    lazy
   [8]:    dog
   [9]:    in
   [10]:    the
   [11]:    barn

The last occurrence of "the" is at index 10.
The last occurrence of "the" between the start and index 8 is at index 6.
The last occurrence of "the" between index 10 and index 5 is at index 10.
*/

Imports System.Collections

Public Class SamplesArrayList
   
   Public Shared Sub Main()
      
      ' Creates and initializes a new ArrayList with three elements of the same value.
      Dim myAL As New ArrayList()
      myAL.Add("the")
      myAL.Add("quick")
      myAL.Add("brown")
      myAL.Add("fox")
      myAL.Add("jumps")
      myAL.Add("over")
      myAL.Add("the")
      myAL.Add("lazy")
      myAL.Add("dog")
      myAL.Add("in")
      myAL.Add("the")
      myAL.Add("barn")
      
      ' Displays the values of the ArrayList.
      Console.WriteLine("The ArrayList contains the following values:")
      PrintIndexAndValues(myAL)
      
      ' Searches for the last occurrence of the duplicated value.
      Dim myString As [String] = "the"
      Dim myIndex As Integer = myAL.LastIndexOf(myString)
      Console.WriteLine("The last occurrence of ""{0}"" is at index {1}.", myString, myIndex)
      
      ' Searches for the last occurrence of the duplicated value in the first section of the ArrayList.
      myIndex = myAL.LastIndexOf(myString, 8)
      Console.WriteLine("The last occurrence of ""{0}"" between the start and index 8 is at index {1}.", myString, myIndex)
      
      ' Searches for the last occurrence of the duplicated value in a section of the ArrayList.  Note that the start index is greater than the end index because the search is done backward.
      myIndex = myAL.LastIndexOf(myString, 10, 6)
      Console.WriteLine("The last occurrence of ""{0}"" between index 10 and index 5 is at index {1}.", myString, myIndex)
   End Sub
   
   
   Public Shared Sub PrintIndexAndValues(myList As IEnumerable)
      Dim i as Integer
      Dim obj As [Object]
      For Each obj In  myList
         Console.WriteLine("   [{0}]:    {1}", i, obj)
         i = i + 1
      Next obj
      Console.WriteLine()
   End Sub

End Class

' This code produces the following output.
'
' The ArrayList contains the following values:
'    [0]:    the
'    [1]:    quick
'    [2]:    brown
'    [3]:    fox
'    [4]:    jumps
'    [5]:    over
'    [6]:    the
'    [7]:    lazy
'    [8]:    dog
'    [9]:    in
'    [10]:    the
'    [11]:    barn
'
' The last occurrence of "the" is at index 10.
' The last occurrence of "the" between the start and index 8 is at index 6.
' The last occurrence of "the" between index 10 and index 5 is at index 10.

注釈

は ArrayList 、最初の要素から startIndex 始まり、最後まで後方に検索されます。

このメソッドは線形検索を実行します。したがって、このメソッドは操作ですO(n)。ここでn、はの先頭からへのstartIndex要素のArrayList数です。

このメソッドは、を呼び出 Object.Equalsして等価性を判断します。

こちらもご覧ください

適用対象

LastIndexOf(Object, Int32, Int32)

Source:: ArrayList.cs

Source:: ArrayList.cs

Source:: ArrayList.cs

指定した Object を検索し、指定した数の要素を含み、かつ指定したインデックスで終了する ArrayList 内の要素の範囲内で最後に出現する位置の 0 から始まるインデックス番号を返します。

public:
 virtual int LastIndexOf(System::Object ^ value, int startIndex, int count);

public virtual int LastIndexOf (object value, int startIndex, int count);

public virtual int LastIndexOf (object? value, int startIndex, int count);

abstract member LastIndexOf : obj * int * int -> int
override this.LastIndexOf : obj * int * int -> int

Public Overridable Function LastIndexOf (value As Object, startIndex As Integer, count As Integer) As Integer

パラメーター

value: Object

ArrayList 内で検索される Object。値として null を指定できます。

startIndex: Int32

後方検索の開始位置を示す 0 から始まるインデックス。

count: Int32

検索対象の範囲内にある要素の数。

戻り値

Int32

count 個の要素を格納し、startIndex の位置で終了する ArrayList 内の要素の範囲内で value が見つかった場合は、最後に見つかった位置の 0 から始まるインデックス番号。それ以外の場合は -1。

例外

ArgumentOutOfRangeException

startIndex は ArrayListの有効なインデックスの範囲外です。

- または -

count が 0 未満です。

- または -

startIndex および count が ArrayList 内の正しいセクションを指定していません。

例

次のコード例は、指定した要素の最後に出現するインデックスを決定する方法を示しています。 LastIndexOfは後方検索であるため、count+ 1 以下startIndexである必要があります。

using namespace System;
using namespace System::Collections;
void PrintIndexAndValues( IEnumerable^ myList );
int main()
{
   
   // Creates and initializes a new ArrayList with three elements of the same value.
   ArrayList^ myAL = gcnew ArrayList;
   myAL->Add( "the" );
   myAL->Add( "quick" );
   myAL->Add( "brown" );
   myAL->Add( "fox" );
   myAL->Add( "jumps" );
   myAL->Add( "over" );
   myAL->Add( "the" );
   myAL->Add( "lazy" );
   myAL->Add( "dog" );
   myAL->Add( "in" );
   myAL->Add( "the" );
   myAL->Add( "barn" );
   
   // Displays the values of the ArrayList.
   Console::WriteLine( "The ArrayList contains the following values:" );
   PrintIndexAndValues( myAL );
   
   // Searches for the last occurrence of the duplicated value.
   String^ myString = "the";
   int myIndex = myAL->LastIndexOf( myString );
   Console::WriteLine( "The last occurrence of \"{0}\" is at index {1}.", myString, myIndex );
   
   // Searches for the last occurrence of the duplicated value in the first section of the ArrayList.
   myIndex = myAL->LastIndexOf( myString, 8 );
   Console::WriteLine( "The last occurrence of \"{0}\" between the start and index 8 is at index {1}.", myString, myIndex );
   
   // Searches for the last occurrence of the duplicated value in a section of the ArrayList.  Note that the start index is greater than the end index because the search is done backward.
   myIndex = myAL->LastIndexOf( myString, 10, 6 );
   Console::WriteLine( "The last occurrence of \"{0}\" between index 10 and index 5 is at index {1}.", myString, myIndex );
}

void PrintIndexAndValues( IEnumerable^ myList )
{
   int i = 0;
   IEnumerator^ myEnum = myList->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::WriteLine( "   [{0}]:    {1}", i++, obj );
   }

   Console::WriteLine();
}

/*
 This code produces the following output.
 
 The ArrayList contains the following values:
    [0]:    the
    [1]:    quick
    [2]:    brown
    [3]:    fox
    [4]:    jumps
    [5]:    over
    [6]:    the
    [7]:    lazy
    [8]:    dog
    [9]:    in
    [10]:    the
    [11]:    barn

 The last occurrence of "the" is at index 10.
 The last occurrence of "the" between the start and index 8 is at index 6.
 The last occurrence of "the" between index 10 and index 5 is at index 10.
 */

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

   public static void Main()  {

      // Creates and initializes a new ArrayList with three elements of the same value.
      ArrayList myAL = new ArrayList();
      myAL.Add( "the" );
      myAL.Add( "quick" );
      myAL.Add( "brown" );
      myAL.Add( "fox" );
      myAL.Add( "jumps" );
      myAL.Add( "over" );
      myAL.Add( "the" );
      myAL.Add( "lazy" );
      myAL.Add( "dog" );
      myAL.Add( "in" );
      myAL.Add( "the" );
      myAL.Add( "barn" );

      // Displays the values of the ArrayList.
      Console.WriteLine( "The ArrayList contains the following values:" );
      PrintIndexAndValues( myAL );

      // Searches for the last occurrence of the duplicated value.
      string myString = "the";
      int myIndex = myAL.LastIndexOf( myString );
      Console.WriteLine( "The last occurrence of \"{0}\" is at index {1}.", myString, myIndex );

      // Searches for the last occurrence of the duplicated value in the first section of the ArrayList.
      myIndex = myAL.LastIndexOf( myString, 8 );
      Console.WriteLine( "The last occurrence of \"{0}\" between the start and index 8 is at index {1}.", myString, myIndex );

      // Searches for the last occurrence of the duplicated value in a section of the ArrayList.  Note that the start index is greater than the end index because the search is done backward.
      myIndex = myAL.LastIndexOf( myString, 10, 6 );
      Console.WriteLine( "The last occurrence of \"{0}\" between index 10 and index 5 is at index {1}.", myString, myIndex );
   }

   public static void PrintIndexAndValues( IEnumerable myList )  {
      int i = 0;
      foreach ( Object obj in myList )
         Console.WriteLine( "   [{0}]:    {1}", i++, obj );
      Console.WriteLine();
   }
}


/*
This code produces the following output.

The ArrayList contains the following values:
   [0]:    the
   [1]:    quick
   [2]:    brown
   [3]:    fox
   [4]:    jumps
   [5]:    over
   [6]:    the
   [7]:    lazy
   [8]:    dog
   [9]:    in
   [10]:    the
   [11]:    barn

The last occurrence of "the" is at index 10.
The last occurrence of "the" between the start and index 8 is at index 6.
The last occurrence of "the" between index 10 and index 5 is at index 10.
*/

Imports System.Collections

Public Class SamplesArrayList
   
   Public Shared Sub Main()
      
      ' Creates and initializes a new ArrayList with three elements of the same value.
      Dim myAL As New ArrayList()
      myAL.Add("the")
      myAL.Add("quick")
      myAL.Add("brown")
      myAL.Add("fox")
      myAL.Add("jumps")
      myAL.Add("over")
      myAL.Add("the")
      myAL.Add("lazy")
      myAL.Add("dog")
      myAL.Add("in")
      myAL.Add("the")
      myAL.Add("barn")
      
      ' Displays the values of the ArrayList.
      Console.WriteLine("The ArrayList contains the following values:")
      PrintIndexAndValues(myAL)
      
      ' Searches for the last occurrence of the duplicated value.
      Dim myString As [String] = "the"
      Dim myIndex As Integer = myAL.LastIndexOf(myString)
      Console.WriteLine("The last occurrence of ""{0}"" is at index {1}.", myString, myIndex)
      
      ' Searches for the last occurrence of the duplicated value in the first section of the ArrayList.
      myIndex = myAL.LastIndexOf(myString, 8)
      Console.WriteLine("The last occurrence of ""{0}"" between the start and index 8 is at index {1}.", myString, myIndex)
      
      ' Searches for the last occurrence of the duplicated value in a section of the ArrayList.  Note that the start index is greater than the end index because the search is done backward.
      myIndex = myAL.LastIndexOf(myString, 10, 6)
      Console.WriteLine("The last occurrence of ""{0}"" between index 10 and index 5 is at index {1}.", myString, myIndex)
   End Sub
   
   
   Public Shared Sub PrintIndexAndValues(myList As IEnumerable)
      Dim i as Integer
      Dim obj As [Object]
      For Each obj In  myList
         Console.WriteLine("   [{0}]:    {1}", i, obj)
         i = i + 1
      Next obj
      Console.WriteLine()
   End Sub

End Class

' This code produces the following output.
'
' The ArrayList contains the following values:
'    [0]:    the
'    [1]:    quick
'    [2]:    brown
'    [3]:    fox
'    [4]:    jumps
'    [5]:    over
'    [6]:    the
'    [7]:    lazy
'    [8]:    dog
'    [9]:    in
'    [10]:    the
'    [11]:    barn
'
' The last occurrence of "the" is at index 10.
' The last occurrence of "the" between the start and index 8 is at index 6.
' The last occurrence of "the" between index 10 and index 5 is at index 10.

注釈

ArrayListが 0 より大きい場合countは、からstartIndex逆方向に検索され、マイナス count 1 で終わるstartIndex。

このメソッドは線形検索を実行します。したがって、このメソッドは操作であり O(n) 、は ncountです。

このメソッドは、を呼び出 Object.Equalsして等価性を判断します。

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適用対象

ArrayList.LastIndexOf メソッド

定義

オーバーロード

LastIndexOf(Object)

パラメーター

戻り値

例

注釈

こちらもご覧ください

適用対象

LastIndexOf(Object, Int32)

パラメーター

戻り値

例外

例

注釈

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適用対象

LastIndexOf(Object, Int32, Int32)

パラメーター

戻り値

例外

例

注釈

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適用対象

フィードバック

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