ArrayList.GetRange(Int32, Int32) Metodo

Definizione

Spazio dei nomi:

System.Collections

Assembly:

System.Runtime.dll

Source:

ArrayList.cs

Restituisce ArrayList che rappresenta un subset di elementi nell'oggetto ArrayList di origine.

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

Parametri

index

Int32

Indice in base zero di ArrayList in corrispondenza del quale inizia la serie.

count

Int32

Numero di elementi nell'intervallo.

Restituisce

ArrayList

Oggetto ArrayList che rappresenta un subset di elementi nell'oggetto ArrayList di origine.

Eccezioni

ArgumentOutOfRangeException

index è minore di zero.

-oppure-

count è minore di zero.

ArgumentException

index e count non indicano un intervallo valido di elementi nell'oggetto ArrayList.

Esempio

Nell'esempio di codice seguente viene illustrato come impostare e ottenere un intervallo di elementi in 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

Commenti

Questo metodo non crea copie degli elementi. Il nuovo ArrayList oggetto è solo una finestra di visualizzazione nell'origine ArrayList. Tuttavia, tutte le modifiche successive all'origine ArrayList devono essere eseguite tramite questa finestra di ArrayListvisualizzazione. Se le modifiche vengono apportate direttamente all'origine ArrayList, la finestra ArrayList di visualizzazione viene invalidata e qualsiasi operazione su di essa restituirà un oggetto InvalidOperationException.

Questo metodo è un'operazione O(1) .

Vedi anche

• RemoveRange(Int32, Int32)
• AddRange(ICollection)
• InsertRange(Int32, ICollection)
• SetRange(Int32, ICollection)