ArrayList.LastIndexOf ArrayList.LastIndexOf ArrayList.LastIndexOf ArrayList.LastIndexOf Method

Definizione

Restituisce l'indice in base zero dell'ultima occorrenza di un valore in ArrayList o in una parte di esso.Returns the zero-based index of the last occurrence of a value in the ArrayList or in a portion of it.

Overload

LastIndexOf(Object) LastIndexOf(Object) LastIndexOf(Object) LastIndexOf(Object)

Cerca l'oggetto Object specificato e restituisce l'indice in base zero dell'ultima occorrenza all'interno dell'insieme ArrayList.Searches for the specified Object and returns the zero-based index of the last occurrence within the entire ArrayList.

LastIndexOf(Object, Int32) LastIndexOf(Object, Int32) LastIndexOf(Object, Int32) LastIndexOf(Object, Int32)

Cerca l'oggetto specificato Object e restituisce l'indice in base zero dell'ultima occorrenza all'interno dell'intervallo di elementi nella classe ArrayList che è compresa tra il primo elemento e l'indice specificato.Searches for the specified Object and returns the zero-based index of the last occurrence within the range of elements in the ArrayList that extends from the first element to the specified index.

LastIndexOf(Object, Int32, Int32) LastIndexOf(Object, Int32, Int32) LastIndexOf(Object, Int32, Int32) LastIndexOf(Object, Int32, Int32)

Cerca l'oggetto Object specificato e restituisce l'indice in base zero dell'ultima occorrenza all'interno dell'intervallo di elementi della classe ArrayList che contiene il numero specificato di elementi e termina in corrispondenza dell'indice specificato.Searches for the specified Object and returns the zero-based index of the last occurrence within the range of elements in the ArrayList that contains the specified number of elements and ends at the specified index.

LastIndexOf(Object) LastIndexOf(Object) LastIndexOf(Object) LastIndexOf(Object)

Cerca l'oggetto Object specificato e restituisce l'indice in base zero dell'ultima occorrenza all'interno dell'insieme ArrayList.Searches for the specified Object and returns the zero-based index of the last occurrence within the entire ArrayList.

public:
 virtual int LastIndexOf(System::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

Parametri

value
Object Object Object Object

Oggetto Object da individuare in ArrayList.The Object to locate in the ArrayList. Il valore può essere null.The value can be null.

Restituisce

Indice in base zero dell'ultima occorrenza di value all'interno dell'intero oggetto ArrayList, se presente; in caso contrario, –1.The zero-based index of the last occurrence of value within the entire the ArrayList, if found; otherwise, -1.

Esempi

Esempio di codice seguente viene illustrato come determinare l'indice dell'ultima occorrenza di un elemento specificato.The following code example shows how to determine the index of the last occurrence of a specified element.

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
Imports System.Collections
Imports Microsoft.VisualBasic

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 'Main
   
   
   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 'PrintIndexAndValues

End Class 'SamplesArrayList

' 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.

Commenti

Il ArrayList viene eseguita la ricerca all'indietro a partire dall'ultimo elemento e termina in corrispondenza del primo elemento.The ArrayList is searched backward starting at the last element and ending at the first element.

Questo metodo esegue una ricerca lineare. di conseguenza, questo metodo è un'operazione O (n) operazione, in cui n è Count.This method performs a linear search; therefore, this method is an O(n) operation, where n is Count.

A partire da .NET Framework 2.0, questo metodo Usa gli oggetti della raccolta Equals e CompareTo metodi su item per determinare se l'elemento esiste.Starting with the .NET Framework 2.0, this method uses the collection's objects' Equals and CompareTo methods on item to determine whether item exists. Nelle versioni precedenti di .NET Framework, questo aspetto è stato effettuato utilizzando il Equals e CompareTo metodi del item parametro per gli oggetti nella raccolta.In the earlier versions of the .NET Framework, this determination was made by using the Equals and CompareTo methods of the item parameter on the objects in the collection.

Vedi anche

LastIndexOf(Object, Int32) LastIndexOf(Object, Int32) LastIndexOf(Object, Int32) LastIndexOf(Object, Int32)

Cerca l'oggetto specificato Object e restituisce l'indice in base zero dell'ultima occorrenza all'interno dell'intervallo di elementi nella classe ArrayList che è compresa tra il primo elemento e l'indice specificato.Searches for the specified Object and returns the zero-based index of the last occurrence within the range of elements in the ArrayList that extends from the first element to the specified index.

public:
 virtual int LastIndexOf(System::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

Parametri

value
Object Object Object Object

Oggetto Object da individuare in ArrayList.The Object to locate in the ArrayList. Il valore può essere null.The value can be null.

startIndex
Int32 Int32 Int32 Int32

Indice iniziale in base zero della ricerca all'indietro.The zero-based starting index of the backward search.

Restituisce

Indice in base zero dell'ultima occorrenza di value all'interno dell'intervallo di elementi dell'oggetto ArrayList compreso tra il primo elemento e startIndex, se presente; in caso contrario, –1.The zero-based index of the last occurrence of value within the range of elements in the ArrayList that extends from the first element to startIndex, if found; otherwise, -1.

Eccezioni

startIndex non è compreso nell'intervallo di indici validi per ArrayList.startIndex is outside the range of valid indexes for the ArrayList.

Esempi

Esempio di codice seguente viene illustrato come determinare l'indice dell'ultima occorrenza di un elemento specificato.The following code example shows how to determine the index of the last occurrence of a specified element.

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
Imports System.Collections
Imports Microsoft.VisualBasic

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 'Main
   
   
   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 'PrintIndexAndValues

End Class 'SamplesArrayList

' 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.

Commenti

Il ArrayList viene eseguita con le versioni precedenti a partire dall'indice startIndex e termina in corrispondenza del primo elemento.The ArrayList is searched backward starting at startIndex and ending at the first element.

Questo metodo esegue una ricerca lineare. di conseguenza, questo metodo è un'operazione O (n) operazione, in cui n è il numero di elementi dall'inizio del ArrayList a startIndex.This method performs a linear search; therefore, this method is an O(n) operation, where n is the number of elements from the beginning of the ArrayList to startIndex.

Questo metodo determina l'uguaglianza chiamando Object.Equals.This method determines equality by calling Object.Equals.

A partire da .NET Framework 2.0, questo metodo Usa gli oggetti della raccolta Equals e CompareTo metodi su item per determinare se l'elemento esiste.Starting with the .NET Framework 2.0, this method uses the collection's objects' Equals and CompareTo methods on item to determine whether item exists. Nelle versioni precedenti di .NET Framework, questo aspetto è stato effettuato utilizzando il Equals e CompareTo metodi del item parametro per gli oggetti nella raccolta.In the earlier versions of the .NET Framework, this determination was made by using the Equals and CompareTo methods of the item parameter on the objects in the collection.

Vedi anche

LastIndexOf(Object, Int32, Int32) LastIndexOf(Object, Int32, Int32) LastIndexOf(Object, Int32, Int32) LastIndexOf(Object, Int32, Int32)

Cerca l'oggetto Object specificato e restituisce l'indice in base zero dell'ultima occorrenza all'interno dell'intervallo di elementi della classe ArrayList che contiene il numero specificato di elementi e termina in corrispondenza dell'indice specificato.Searches for the specified Object and returns the zero-based index of the last occurrence within the range of elements in the ArrayList that contains the specified number of elements and ends at the specified index.

public:
 virtual int LastIndexOf(System::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

Parametri

value
Object Object Object Object

Oggetto Object da individuare in ArrayList.The Object to locate in the ArrayList. Il valore può essere null.The value can be null.

startIndex
Int32 Int32 Int32 Int32

Indice iniziale in base zero della ricerca all'indietro.The zero-based starting index of the backward search.

count
Int32 Int32 Int32 Int32

Numero di elementi nella sezione in cui eseguire la ricerca.The number of elements in the section to search.

Restituisce

Indice in base zero dell'ultima occorrenza di value all'interno dell'intervallo di elementi in ArrayList che contiene un numero di elementi corrispondente a count e termina in corrispondenza di startIndex, se presente; in caso contrario, -1.The zero-based index of the last occurrence of value within the range of elements in the ArrayList that contains count number of elements and ends at startIndex, if found; otherwise, -1.

Eccezioni

startIndex non è compreso nell'intervallo di indici validi per ArrayList.startIndex is outside the range of valid indexes for the ArrayList.

In alternativa-or- count è minore di zero.count is less than zero.

In alternativa-or- startIndex e count non specificano una sezione valida in ArrayList.startIndex and count do not specify a valid section in the ArrayList.

Esempi

Esempio di codice seguente viene illustrato come determinare l'indice dell'ultima occorrenza di un elemento specificato.The following code example shows how to determine the index of the last occurrence of a specified element. Si noti che LastIndexOf è una ricerca all'indietro, pertanto count deve essere minore o uguale a startIndex + 1.Note that LastIndexOf is a backward search; therefore, count must be less than or equal to 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
Imports System.Collections
Imports Microsoft.VisualBasic

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 'Main
   
   
   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 'PrintIndexAndValues

End Class 'SamplesArrayList

' 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.

Commenti

Il ArrayList viene eseguita con le versioni precedenti a partire dall'indice startIndex a startIndex meno count + 1, se count è maggiore di 0.The ArrayList is searched backward starting at startIndex and ending at startIndex minus count plus 1, if count is greater than 0.

Questo metodo esegue una ricerca lineare. di conseguenza, questo metodo è un'operazione O (n) operazione, in cui n è count.This method performs a linear search; therefore, this method is an O(n) operation, where n is count.

Questo metodo determina l'uguaglianza chiamando Object.Equals.This method determines equality by calling Object.Equals.

A partire da .NET Framework 2.0, questo metodo Usa gli oggetti della raccolta Equals e CompareTo metodi su item per determinare se l'elemento esiste.Starting with the .NET Framework 2.0, this method uses the collection's objects' Equals and CompareTo methods on item to determine whether item exists. Nelle versioni precedenti di .NET Framework, questo aspetto è stato effettuato utilizzando il Equals e CompareTo metodi del item parametro per gli oggetti nella raccolta.In the earlier versions of the .NET Framework, this determination was made by using the Equals and CompareTo methods of the item parameter on the objects in the collection.

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