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ArrayList.LastIndexOf Método

Definición

Devuelve el índice de base cero de la última aparición de un valor en el ArrayList o en una parte de él.

Sobrecargas

LastIndexOf(Object)

Busca el Object especificado y devuelve el índice de base cero de la última aparición en toda la ArrayList.

LastIndexOf(Object, Int32)

Busca el Object especificado y devuelve el índice de base cero de la última aparición dentro del intervalo de elementos del ArrayList que se extiende desde el primer elemento al índice especificado.

LastIndexOf(Object, Int32, Int32)

Busca el Object especificado y devuelve el índice de base cero de la última aparición dentro del intervalo de elementos de la ArrayList que contiene el número especificado de elementos y termina en el índice especificado.

LastIndexOf(Object)

Source:
ArrayList.cs
Source:
ArrayList.cs
Source:
ArrayList.cs

Busca el Object especificado y devuelve el índice de base cero de la última aparición en toda la ArrayList.

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

Parámetros

value
Object

El Object que se va a buscar en el ArrayList. El valor puede ser null.

Devoluciones

Índice de base cero de la última aparición de value dentro de toda la ArrayList, si se encuentra; de lo contrario, -1.

Ejemplos

En el ejemplo de código siguiente se muestra cómo determinar el índice de la última aparición de un elemento especificado.

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.

Comentarios

El ArrayList se busca hacia atrás a partir del último elemento y termina en el primer elemento.

Este método realiza una búsqueda lineal; por lo tanto, este método es una operación de O(n), donde n es Count.

A partir de .NET Framework 2.0, este método usa los métodos Equals y CompareTo de los objetos de la colección en item para determinar si existe un elemento. En las versiones anteriores de .NET Framework, esta determinación se realizó mediante los métodos Equals y CompareTo del parámetro item en los objetos de la colección.

Consulte también

Se aplica a

LastIndexOf(Object, Int32)

Source:
ArrayList.cs
Source:
ArrayList.cs
Source:
ArrayList.cs

Busca el Object especificado y devuelve el índice de base cero de la última aparición dentro del intervalo de elementos del ArrayList que se extiende desde el primer elemento al índice especificado.

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

Parámetros

value
Object

El Object que se va a buscar en el ArrayList. El valor puede ser null.

startIndex
Int32

Índice inicial de base cero de la búsqueda hacia atrás.

Devoluciones

Índice de base cero de la última aparición de value dentro del intervalo de elementos del ArrayList que se extiende desde el primer elemento hasta startIndex, si se encuentra; de lo contrario, -1.

Excepciones

startIndex está fuera del intervalo de índices válidos para el ArrayList.

Ejemplos

En el ejemplo de código siguiente se muestra cómo determinar el índice de la última aparición de un elemento especificado.

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.

Comentarios

El ArrayList se busca hacia atrás a partir de startIndex y termina en el primer elemento.

Este método realiza una búsqueda lineal; por lo tanto, este método es una operación de O(n), donde n es el número de elementos desde el principio del ArrayList hasta startIndex.

Este método determina la igualdad llamando a Object.Equals.

A partir de .NET Framework 2.0, este método usa los métodos Equals y CompareTo de los objetos de la colección en item para determinar si existe un elemento. En las versiones anteriores de .NET Framework, esta determinación se realizó mediante los métodos Equals y CompareTo del parámetro item en los objetos de la colección.

Consulte también

Se aplica a

LastIndexOf(Object, Int32, Int32)

Source:
ArrayList.cs
Source:
ArrayList.cs
Source:
ArrayList.cs

Busca el Object especificado y devuelve el índice de base cero de la última aparición dentro del intervalo de elementos de la ArrayList que contiene el número especificado de elementos y termina en el índice especificado.

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

Parámetros

value
Object

El Object que se va a buscar en el ArrayList. El valor puede ser null.

startIndex
Int32

Índice inicial de base cero de la búsqueda hacia atrás.

count
Int32

Número de elementos de la sección que se va a buscar.

Devoluciones

Índice de base cero de la última aparición de value dentro del intervalo de elementos del ArrayList que contiene count número de elementos y termina en startIndex, si se encuentra; de lo contrario, -1.

Excepciones

startIndex está fuera del intervalo de índices válidos para el ArrayList.

-o-

count es menor que cero.

-o-

startIndex y count no especifican una sección válida en el ArrayList.

Ejemplos

En el ejemplo de código siguiente se muestra cómo determinar el índice de la última aparición de un elemento especificado. Tenga en cuenta que LastIndexOf es una búsqueda hacia atrás; por lo tanto, count debe ser menor o igual que startIndex + 1.

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.

Comentarios

El ArrayList se busca hacia atrás a partir de startIndex y termina en startIndex menos count más 1, si count es mayor que 0.

Este método realiza una búsqueda lineal; por lo tanto, este método es una operación de O(n), donde n es count.

Este método determina la igualdad llamando a Object.Equals.

A partir de .NET Framework 2.0, este método usa los métodos Equals y CompareTo de los objetos de la colección en item para determinar si existe un elemento. En las versiones anteriores de .NET Framework, esta determinación se realizó mediante los métodos Equals y CompareTo del parámetro item en los objetos de la colección.

Consulte también

Se aplica a