ArrayList.RemoveAt Method
Removes the element at the specified index of the ArrayList.
Namespace: System.Collections
Assembly: mscorlib (in mscorlib.dll)
Parameters
- index
- Type: System.Int32
The zero-based index of the element to remove.
Implements
IList.RemoveAt(Int32)| Exception | 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. |
After the element is removed, the size of the collection is adjusted and the value of the Count property is decreased by one.
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 hash table.
This method is an O(n) operation, where n is Count.
The following code example shows how to remove elements from the ArrayList.
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 ) { 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 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 */
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.