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ArrayList.RemoveRange(Int32, Int32) Metoda

Definicja

Usuwa zakres elementów z elementu ArrayList.

public:
 virtual void RemoveRange(int index, int count);
public virtual void RemoveRange (int index, int count);
abstract member RemoveRange : int * int -> unit
override this.RemoveRange : int * int -> unit
Public Overridable Sub RemoveRange (index As Integer, count As Integer)

Parametry

index
Int32

Zerowy indeks początkowy zakresu elementów do usunięcia.

count
Int32

Liczba elementów do usunięcia.

Wyjątki

Parametr index ma wartość niższą niż zero.

-lub-

Parametr count ma wartość niższą niż zero.

index i count nie oznaczają prawidłowego zakresu elementów w obiekcie ArrayList.

Element ArrayList jest tylko do odczytu.

-lub-

Element ArrayList ma stały rozmiar.

Przykłady

Poniższy przykład kodu pokazuje, jak usunąć elementy z elementu ArrayList.

using namespace System;
using namespace System::Collections;
void PrintValues( IEnumerable^ myList );
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" );
   
   // Displays the ArrayList.
   Console::WriteLine( "The ArrayList initially contains the following:" );
   PrintValues( myAL );
   
   // Removes the element containing "lazy".
   myAL->Remove( "lazy" );
   
   // Displays the current state of the ArrayList.
   Console::WriteLine( "After removing \"lazy\":" );
   PrintValues( myAL );
   
   // Removes the element at index 5.
   myAL->RemoveAt( 5 );
   
   // Displays the current state of the ArrayList.
   Console::WriteLine( "After removing the element at index 5:" );
   PrintValues( myAL );
   
   // Removes three elements starting at index 4.
   myAL->RemoveRange( 4, 3 );
   
   // Displays the current state of the ArrayList.
   Console::WriteLine( "After removing three elements starting at index 4:" );
   PrintValues( myAL );
}

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

   Console::WriteLine();
}

/* 
 This code produces the following output.
 
 The ArrayList initially contains the following:
    The   quick   brown   fox   jumps   over   the   lazy   dog
 After removing "lazy":
    The   quick   brown   fox   jumps   over   the   dog
 After removing the element at index 5:
    The   quick   brown   fox   jumps   the   dog
 After removing three elements starting at index 4:
    The   quick   brown   fox
 */
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" );

      // Displays the ArrayList.
      Console.WriteLine( "The ArrayList initially contains the following:" );
      PrintValues( myAL );

      // Removes the element containing "lazy".
      myAL.Remove( "lazy" );

      // Displays the current state of the ArrayList.
      Console.WriteLine( "After removing \"lazy\":" );
      PrintValues( myAL );

      // Removes the element at index 5.
      myAL.RemoveAt( 5 );

      // Displays the current state of the ArrayList.
      Console.WriteLine( "After removing the element at index 5:" );
      PrintValues( myAL );

      // Removes three elements starting at index 4.
      myAL.RemoveRange( 4, 3 );

      // Displays the current state of the ArrayList.
      Console.WriteLine( "After removing three elements starting at index 4:" );
      PrintValues( myAL );
   }

   public static void PrintValues( IEnumerable myList )  {
      foreach ( Object obj in myList )
         Console.Write( "   {0}", obj );
      Console.WriteLine();
   }
}
/*
This code produces the following output.

The ArrayList initially contains the following:
   The   quick   brown   fox   jumps   over   the   lazy   dog
After removing "lazy":
   The   quick   brown   fox   jumps   over   the   dog
After removing the element at index 5:
   The   quick   brown   fox   jumps   the   dog
After removing three elements starting at index 4:
   The   quick   brown   fox
*/
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")
        
        ' Displays the ArrayList.
        Console.WriteLine("The ArrayList initially contains the following:")
        PrintValues(myAL)
        
        ' Removes the element containing "lazy".
        myAL.Remove("lazy")
        
        ' Displays the current state of the ArrayList.
        Console.WriteLine("After removing ""lazy"":")
        PrintValues(myAL)
        
        ' Removes the element at index 5.
        myAL.RemoveAt(5)
        
        ' Displays the current state of the ArrayList.
        Console.WriteLine("After removing the element at index 5:")
        PrintValues(myAL)
        
        ' Removes three elements starting at index 4.
        myAL.RemoveRange(4, 3)
        
        ' Displays the current state of the ArrayList.
        Console.WriteLine("After removing three elements starting at index 4:")
        PrintValues(myAL)
    End Sub
    
    Public Shared Sub PrintValues(myList As IEnumerable)
        Dim obj As [Object]
        For Each obj In  myList
            Console.Write("   {0}", obj)
        Next obj
        Console.WriteLine()
    End Sub

End Class


' This code produces the following output.
' 
' The ArrayList initially contains the following:
'    The   quick   brown   fox   jumps   over   the   lazy   dog
' After removing "lazy":
'    The   quick   brown   fox   jumps   over   the   dog
' After removing the element at index 5:
'    The   quick   brown   fox   jumps   the   dog
' After removing three elements starting at index 4:
'    The   quick   brown   fox

Uwagi

W kolekcjach ciągłych elementów, takich jak listy, elementy, które podążają za usuniętym elementem, są przenoszone w górę, aby zajmować opuszczone miejsce. Jeśli kolekcja jest indeksowana, indeksy przeniesionych elementów również są aktualizowane. To zachowanie nie dotyczy kolekcji, w których elementy są pod względem koncepcyjnym pogrupowane w przedziały, np. tablic skrótów.

Ta metoda jest operacją O(n) , gdzie n to Count.

Dotyczy

Zobacz też