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ArrayList.RemoveAt Method

Removes the element at the specified index of the ArrayList.

[Visual Basic]
Public Overridable Sub RemoveAt( _
   ByVal index As Integer _
) Implements IList.RemoveAt
[C#]
public virtual void RemoveAt(
 int index
);
[C++]
public: virtual void RemoveAt(
 int index
);
[JScript]
public function RemoveAt(
   index : int
);

Parameters

index
The zero-based index of the element to remove.

Implements

IList.RemoveAt

Exceptions

Exception Type Condition
ArgumentOutOfRangeException index is less than zero.

-or-

index is equal to or greater than Count.

NotSupportedException The ArrayList is read-only.

-or-

The ArrayList has a fixed size.

Remarks

In collections of contiguous elements, such as lists, the elements that follow the removed element move up to occupy the vacated spot. If the collection is indexed, the indexes of the elements that are moved are also updated. This behavior does not apply to collections where elements are conceptually grouped into buckets, such as a hashtable.

Example

The following example shows how to remove elements from the ArrayList.

[Visual Basic] 
Imports System
Imports System.Collections
Imports Microsoft.VisualBasic

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("jumped")
        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 myEnumerator As System.Collections.IEnumerator = _
           myList.GetEnumerator()
        While myEnumerator.MoveNext()
            Console.Write(ControlChars.Tab + "{0}", myEnumerator.Current)
        End While
        Console.WriteLine()
    End Sub
End Class

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

[C#] 
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( "jumped" );
      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 )  {
      System.Collections.IEnumerator myEnumerator = myList.GetEnumerator();
      while ( myEnumerator.MoveNext() )
         Console.Write( "\t{0}", myEnumerator.Current );
      Console.WriteLine();
   }
}
/* 
This code produces the following output.

The ArrayList initially contains the following:
    The    quick    brown    fox    jumped    over    the    lazy    dog
After removing "lazy":
    The    quick    brown    fox    jumped    over    the    dog
After removing the element at index 5:
    The    quick    brown    fox    jumped    the    dog
After removing three elements starting at index 4:
    The    quick    brown    fox
*/ 

[C++] 
#using <mscorlib.dll>
using namespace System;
using namespace System::Collections;

void PrintValues( IEnumerable* myList );
 
int main()  {
 
       // Creates and initializes a new ArrayList.
       ArrayList* myAL = new ArrayList();
       myAL->Add( S"The" );
       myAL->Add( S"quick" );
       myAL->Add( S"brown" );
       myAL->Add( S"fox" );
       myAL->Add( S"jumped" );
       myAL->Add( S"over" );
       myAL->Add( S"the" );
       myAL->Add( S"lazy" );
       myAL->Add( S"dog" );
 
       // Displays the ArrayList.
       Console::WriteLine( "The ArrayList initially contains the following:" );
       PrintValues( myAL );
 
       // Removes the element containing "lazy".
       myAL->Remove( S"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 )  {
       System::Collections::IEnumerator* myEnumerator = myList->GetEnumerator();
       while ( myEnumerator->MoveNext() )
          Console::Write( "\t{0}", myEnumerator->Current );
       Console::WriteLine();
    }

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

 */ 

[JScript] 
import System;
import System.Collections;

// Creates and initializes a new ArrayList.
var myAL : ArrayList = new ArrayList();
myAL.Add( "The" );
myAL.Add( "quick" );
myAL.Add( "brown" );
myAL.Add( "fox" );
myAL.Add( "jumped" );
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 );

function PrintValues( myList : IEnumerable )  {
   var myEnumerator : System.Collections.IEnumerator  = myList.GetEnumerator();
   while ( myEnumerator.MoveNext() )
      Console.Write( "\t{0}", myEnumerator.Current );
   Console.WriteLine();
}
 /* 
 This code produces the following output.
 
 The ArrayList initially contains the following:
     The    quick    brown    fox    jumped    over    the    lazy    dog
 After removing "lazy":
     The    quick    brown    fox    jumped    over    the    dog
 After removing the element at index 5:
     The    quick    brown    fox    jumped    the    dog
 After removing three elements starting at index 4:
     The    quick    brown    fox
 */ 

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework, Common Language Infrastructure (CLI) Standard

See Also

ArrayList Class | ArrayList Members | System.Collections Namespace | Remove | RemoveRange | Add | Insert

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