ArrayList.RemoveAt-Methode
Entfernt das Element am angegebenen Index aus der ArrayList.
Namespace: System.Collections
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public Overridable Sub RemoveAt ( _
index As Integer _
)
'Usage
Dim instance As ArrayList
Dim index As Integer
instance.RemoveAt(index)
public virtual void RemoveAt (
int index
)
public:
virtual void RemoveAt (
int index
)
public void RemoveAt (
int index
)
public function RemoveAt (
index : int
)
Parameter
- index
Der nullbasierte Index des zu entfernenden Elements.
Ausnahmen
| Ausnahmetyp | Bedingung |
|---|---|
index ist kleiner als 0 (null). – oder – index ist größer oder gleich Count. |
|
ArrayList ist schreibgeschützt. – oder – ArrayList hat eine feste Größe. |
Hinweise
In Auflistungen mit zusammenhängenden Elementen, z. B. Listen, wird die entstandene Lücke durch Verschieben aller nachfolgenden Elemente gefüllt. Wenn die Auflistung indiziert ist, werden auch die Indizes der verschobenen Elemente aktualisiert. Dies gilt nicht für Auflistungen, in denen die Elemente konzeptionell in Buckets gruppiert sind, z. B. Hashtabellen.
Diese Methode ist eine O(n)-Operation, wobei n der Count ist.
Beispiel
Im folgenden Codebeispiel wird veranschaulicht, wie Elemente aus ArrayList entfernt werden.
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 obj As [Object]
For Each obj In myList
Console.Write(" {0}", obj)
Next obj
Console.WriteLine()
End Sub 'PrintValues
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
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
*/
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( "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 );
}
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 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
*/
import System.*;
import System.Collections.*;
public class SamplesArrayList
{
public static void main(String[] args)
{
// 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);
} //main
public static void PrintValues(IEnumerable myList)
{
IEnumerator objMyEnum = myList.GetEnumerator();
while (objMyEnum.MoveNext()) {
Object obj = objMyEnum.get_Current();
Console.Write(" {0}", obj);
}
Console.WriteLine();
} //PrintValues
} //SamplesArrayList
/*
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
*/
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
*/
Plattformen
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile für Pocket PC, Windows Mobile für Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.
Versionsinformationen
.NET Framework
Unterstützt in: 2.0, 1.1, 1.0
.NET Compact Framework
Unterstützt in: 2.0, 1.0
Siehe auch
Referenz
ArrayList-Klasse
ArrayList-Member
System.Collections-Namespace
Remove
RemoveRange
Add
Insert