StringCollection.RemoveAt(Int32) Método

Definición

Espacio de nombres:

System.Collections.Specialized

Ensamblado:

System.Collections.Specialized.dll

Source:

StringCollection.cs

Quita la cadena del índice especificado de StringCollection.

public:
 virtual void RemoveAt(int index);

public void RemoveAt (int index);

abstract member RemoveAt : int -> unit
override this.RemoveAt : int -> unit

Public Sub RemoveAt (index As Integer)

Parámetros

index

Int32

Índice de base cero de la cadena que se va a quitar.

Implementaciones

RemoveAt(Int32)

Excepciones

ArgumentOutOfRangeException

index es menor que cero.

O bien

index es igual o mayor que Count.

Ejemplos

En el ejemplo de código siguiente se quitan los elementos de .StringCollection

#using <System.dll>

using namespace System;
using namespace System::Collections;
using namespace System::Collections::Specialized;
void PrintValues( IEnumerable^ myCol );
int main()
{
   
   // Creates and initializes a new StringCollection.
   StringCollection^ myCol = gcnew StringCollection;
   array<String^>^myArr = {"RED","orange","yellow","RED","green","blue","RED","indigo","violet","RED"};
   myCol->AddRange( myArr );
   Console::WriteLine( "Initial contents of the StringCollection:" );
   PrintValues( myCol );
   
   // Removes one element from the StringCollection.
   myCol->Remove( "yellow" );
   Console::WriteLine( "After removing \"yellow\":" );
   PrintValues( myCol );
   
   // Removes all occurrences of a value from the StringCollection.
   int i = myCol->IndexOf( "RED" );
   while ( i > -1 )
   {
      myCol->RemoveAt( i );
      i = myCol->IndexOf( "RED" );
   }

   Console::WriteLine( "After removing all occurrences of \"RED\":" );
   PrintValues( myCol );
   
   // Clears the entire collection.
   myCol->Clear();
   Console::WriteLine( "After clearing the collection:" );
   PrintValues( myCol );
}

void PrintValues( IEnumerable^ myCol )
{
   IEnumerator^ myEnum = myCol->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::WriteLine( "   {0}", obj );
   }

   Console::WriteLine();
}

/*
This code produces the following output.

Initial contents of the StringCollection:
   RED
   orange
   yellow
   RED
   green
   blue
   RED
   indigo
   violet
   RED

After removing "yellow":
   RED
   orange
   RED
   green
   blue
   RED
   indigo
   violet
   RED

After removing all occurrences of "RED":
   orange
   green
   blue
   indigo
   violet

After clearing the collection:

*/

using System;
using System.Collections;
using System.Collections.Specialized;

public class SamplesStringCollection  {

   public static void Main()  {

      // Creates and initializes a new StringCollection.
      StringCollection myCol = new StringCollection();
      String[] myArr = new String[] { "RED", "orange", "yellow", "RED", "green", "blue", "RED", "indigo", "violet", "RED" };
      myCol.AddRange( myArr );

      Console.WriteLine( "Initial contents of the StringCollection:" );
      PrintValues( myCol );

      // Removes one element from the StringCollection.
      myCol.Remove( "yellow" );

      Console.WriteLine( "After removing \"yellow\":" );
      PrintValues( myCol );

      // Removes all occurrences of a value from the StringCollection.
      int i = myCol.IndexOf( "RED" );
      while ( i > -1 )  {
         myCol.RemoveAt( i );
         i = myCol.IndexOf( "RED" );
      }

      Console.WriteLine( "After removing all occurrences of \"RED\":" );
      PrintValues( myCol );

      // Clears the entire collection.
      myCol.Clear();

      Console.WriteLine( "After clearing the collection:" );
      PrintValues( myCol );
   }

   public static void PrintValues( IEnumerable myCol )  {
      foreach ( Object obj in myCol )
         Console.WriteLine( "   {0}", obj );
      Console.WriteLine();
   }
}

/*
This code produces the following output.

Initial contents of the StringCollection:
   RED
   orange
   yellow
   RED
   green
   blue
   RED
   indigo
   violet
   RED

After removing "yellow":
   RED
   orange
   RED
   green
   blue
   RED
   indigo
   violet
   RED

After removing all occurrences of "RED":
   orange
   green
   blue
   indigo
   violet

After clearing the collection:

*/

Imports System.Collections
Imports System.Collections.Specialized

Public Class SamplesStringCollection   

   Public Shared Sub Main()

      ' Creates and initializes a new StringCollection.
      Dim myCol As New StringCollection()
      Dim myArr() As [String] = {"RED", "orange", "yellow", "RED", "green", "blue", "RED", "indigo", "violet", "RED"}
      myCol.AddRange(myArr)

      Console.WriteLine("Initial contents of the StringCollection:")
      PrintValues(myCol)

      ' Removes one element from the StringCollection.
      myCol.Remove("yellow")

      Console.WriteLine("After removing ""yellow"":")
      PrintValues(myCol)

      ' Removes all occurrences of a value from the StringCollection.
      Dim i As Integer = myCol.IndexOf("RED")
      While i > - 1
         myCol.RemoveAt(i)
         i = myCol.IndexOf("RED")
      End While

      Console.WriteLine("After removing all occurrences of ""RED"":")
      PrintValues(myCol)

      ' Clears the entire collection.
      myCol.Clear()

      Console.WriteLine("After clearing the collection:")
      PrintValues(myCol)

   End Sub

   Public Shared Sub PrintValues(myCol As IEnumerable)
      Dim obj As [Object]
      For Each obj In  myCol
         Console.WriteLine("   {0}", obj)
      Next obj
      Console.WriteLine()
   End Sub

End Class


'This code produces the following output.
'
'Initial contents of the StringCollection:
'   RED
'   orange
'   yellow
'   RED
'   green
'   blue
'   RED
'   indigo
'   violet
'   RED
'
'After removing "yellow":
'   RED
'   orange
'   RED
'   green
'   blue
'   RED
'   indigo
'   violet
'   RED
'
'After removing all occurrences of "RED":
'   orange
'   green
'   blue
'   indigo
'   violet
'
'After clearing the collection:
'

Comentarios

En colecciones de elementos contiguos, como listas, los elementos que van a continuación del elemento eliminado se desplazan hacia arriba para ocupar el espacio libre. Si la colección está indizada, también se actualizan los índices de los elementos que se han movido. Este comportamiento no se aplica a las colecciones cuyos elementos se agrupan conceptualmente en sectores de almacenamiento, como una tabla hash.

Este método es una operación O(n), donde n es Count.