ArrayList.RemoveRange(Int32, Int32) Metodo
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Rimuove un intervallo di elementi da 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)
Parametri
- index
- Int32
Indice iniziale in base zero dell'intervallo di elementi da rimuovere.
- count
- Int32
Numero di elementi da rimuovere.
Eccezioni
index
e count
non indicano un intervallo valido di elementi nell'oggetto ArrayList.
Esempio
Nell'esempio ArrayListdi codice seguente viene illustrato come rimuovere gli elementi da .
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
Commenti
In raccolte di elementi adiacenti, quali gli elenchi, gli elementi successivi al punto di inserimento vengono spostati verso il basso per consentire l'inserimento del nuovo elemento. Se la raccolta è indicizzata, vengono aggiornati anche gli indici degli elementi spostati. Questo comportamento non viene applicato alle raccolte in cui gli elementi sono raggruppati concettualmente in bucket, come accade ad esempio per le tabelle hash.
Questo metodo è un'operazione O(n)
, dove n
è Count.