Comparteix a través de


ArrayList.GetRange(Int32, Int32) Método

Definición

Devuelve una ArrayList que representa un subconjunto de los elementos de la ArrayList de origen.

public:
 virtual System::Collections::ArrayList ^ GetRange(int index, int count);
public virtual System.Collections.ArrayList GetRange (int index, int count);
abstract member GetRange : int * int -> System.Collections.ArrayList
override this.GetRange : int * int -> System.Collections.ArrayList
Public Overridable Function GetRange (index As Integer, count As Integer) As ArrayList

Parámetros

index
Int32

Índice de ArrayList de base cero en el que empieza el intervalo.

count
Int32

Número de elementos del intervalo.

Devoluciones

ArrayList que representa un subconjunto de los elementos de la ArrayList de origen.

Excepciones

index es menor que cero.

O bien

count es menor que cero.

index y count no denotan un intervalo válido de elementos en la ArrayList.

Ejemplos

En el ejemplo de código siguiente se muestra cómo establecer y obtener un intervalo de elementos en .ArrayList

using namespace System;
using namespace System::Collections;
void PrintValues( IEnumerable^ myList, char mySeparator );
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( "jumps" );
   myAL->Add( "over" );
   myAL->Add( "the" );
   myAL->Add( "lazy" );
   myAL->Add( "dog" );
   
   // Creates and initializes the source ICollection.
   Queue^ mySourceList = gcnew Queue;
   mySourceList->Enqueue( "big" );
   mySourceList->Enqueue( "gray" );
   mySourceList->Enqueue( "wolf" );
   
   // Displays the values of five elements starting at index 0.
   ArrayList^ mySubAL = myAL->GetRange( 0, 5 );
   Console::WriteLine( "Index 0 through 4 contains:" );
   PrintValues( mySubAL, '\t' );
   
   // Replaces the values of five elements starting at index 1 with the values in the ICollection.
   myAL->SetRange( 1, mySourceList );
   
   // Displays the values of five elements starting at index 0.
   mySubAL = myAL->GetRange( 0, 5 );
   Console::WriteLine( "Index 0 through 4 now contains:" );
   PrintValues( mySubAL, '\t' );
}

void PrintValues( IEnumerable^ myList, char mySeparator )
{
   IEnumerator^ myEnum = myList->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::Write( "{0}{1}", mySeparator, obj );
   }

   Console::WriteLine();
}

/* 
 This code produces the following output.
 
 Index 0 through 4 contains:
         The     quick   brown   fox     jumps
 Index 0 through 4 now contains:
         The     big     gray    wolf    jumps
 */
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( "jumps" );
      myAL.Add( "over" );
      myAL.Add( "the" );
      myAL.Add( "lazy" );
      myAL.Add( "dog" );

      // Creates and initializes the source ICollection.
      Queue mySourceList = new Queue();
      mySourceList.Enqueue( "big" );
      mySourceList.Enqueue( "gray" );
      mySourceList.Enqueue( "wolf" );

      // Displays the values of five elements starting at index 0.
      ArrayList mySubAL = myAL.GetRange( 0, 5 );
      Console.WriteLine( "Index 0 through 4 contains:" );
      PrintValues( mySubAL, '\t' );

      // Replaces the values of five elements starting at index 1 with the values in the ICollection.
      myAL.SetRange( 1, mySourceList );

      // Displays the values of five elements starting at index 0.
      mySubAL = myAL.GetRange( 0, 5 );
      Console.WriteLine( "Index 0 through 4 now contains:" );
      PrintValues( mySubAL, '\t' );
   }

   public static void PrintValues( IEnumerable myList, char mySeparator )  {
      foreach ( Object obj in myList )
         Console.Write( "{0}{1}", mySeparator, obj );
      Console.WriteLine();
   }
}


/*
This code produces the following output.

Index 0 through 4 contains:
        The     quick   brown   fox     jumps
Index 0 through 4 now contains:
        The     big     gray    wolf    jumps
*/
Imports System.Collections

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("jumps")
        myAL.Add("over")
        myAL.Add("the")
        myAL.Add("lazy")
        myAL.Add("dog")

        ' Creates and initializes the source ICollection.
        Dim mySourceList As New Queue()
        mySourceList.Enqueue("big")
        mySourceList.Enqueue("gray")
        mySourceList.Enqueue("wolf")

        ' Displays the values of five elements starting at index 0.
        Dim mySubAL As ArrayList = myAL.GetRange(0, 5)
        Console.WriteLine("Index 0 through 4 contains:")
        PrintValues(mySubAL, vbTab)

        ' Replaces the values of five elements starting at index 1 with the values in the ICollection.
        myAL.SetRange(1, mySourceList)

        ' Displays the values of five elements starting at index 0.
        mySubAL = myAL.GetRange(0, 5)
        Console.WriteLine("Index 0 through 4 now contains:")
        PrintValues(mySubAL, vbTab)

    End Sub

    Public Shared Sub PrintValues(myList As IEnumerable, mySeparator As Char)
        Dim obj As [Object]
        For Each obj In  myList
            Console.Write("{0}{1}", mySeparator, obj)
        Next obj
        Console.WriteLine()
    End Sub

End Class


' This code produces the following output.
' 
' Index 0 through 4 contains:
'         The     quick   brown   fox     jumps
' Index 0 through 4 now contains:
'         The     big     gray    wolf    jumps

Comentarios

Este método no crea copias de los elementos. El nuevo ArrayList es solo una ventana de vista en el origen ArrayList. Sin embargo, todos los cambios posteriores en el origen ArrayList se deben realizar a través de esta ventana ArrayListde vista . Si los cambios se realizan directamente en el origen ArrayList, la ventana ArrayList de vista se invalida y las operaciones en ella devolverán .InvalidOperationException

Este método es una O(1) operación.

Se aplica a

Consulte también