ArrayList.Remove(Object) Method

public:
 virtual void Remove(System::Object ^ obj);

public virtual void Remove(object obj);

public virtual void Remove(object? obj);

abstract member Remove : obj -> unit
override this.Remove : obj -> unit

Public Overridable Sub Remove (obj As Object)

Parameters

Implements

Exceptions

Examples

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( "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

Remarks

If the ArrayList does not contain the specified object, the ArrayList remains unchanged. No exception is thrown.

This method performs a linear search; therefore, this method is an O(n) operation, where n is Count.

This method determines equality by calling Object.Equals.

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.

See also

• RemoveAt(Int32)
• RemoveRange(Int32, Int32)
• Add(Object)
• Insert(Int32, Object)
• Performing Culture-Insensitive String Operations in Collections