StringEnumerator.MoveNext StringEnumerator.MoveNext StringEnumerator.MoveNext StringEnumerator.MoveNext Method

Definición

Desplaza el enumerador al siguiente elemento de la colección.Advances the enumerator to the next element of the collection.

public:
 bool MoveNext();
public bool MoveNext ();
member this.MoveNext : unit -> bool
Public Function MoveNext () As Boolean

Devoluciones

Es true si el enumerador avanzó con éxito hasta el siguiente elemento; es false si el enumerador alcanzó el final de la colección.true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection.

Excepciones

La colección se modificó después de que el enumerador se creara.The collection was modified after the enumerator was created.

Ejemplos

En el ejemplo de código siguiente se muestra algunas de las propiedades y métodos de StringEnumerator.The following code example demonstrates several of the properties and methods of StringEnumerator.

#using <System.dll>

using namespace System;
using namespace System::Collections::Specialized;
int main()
{
   
   // Creates and initializes a StringCollection.
   StringCollection^ myCol = gcnew StringCollection;
   array<String^>^myArr = {"red","orange","yellow","green","blue","indigo","violet"};
   myCol->AddRange( myArr );
   
   // Enumerates the elements in the StringCollection.
   StringEnumerator^ myEnumerator = myCol->GetEnumerator();
   while ( myEnumerator->MoveNext() )
      Console::WriteLine( "{0}", myEnumerator->Current );

   Console::WriteLine();
   
   // Resets the enumerator and displays the first element again.
   myEnumerator->Reset();
   if ( myEnumerator->MoveNext() )
      Console::WriteLine( "The first element is {0}.", myEnumerator->Current );
}

/*
This code produces the following output.

red
orange
yellow
green
blue
indigo
violet

The first element is red.

*/
using System;
using System.Collections.Specialized;

public class SamplesStringEnumerator  {

   public static void Main()  {

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

      // Enumerates the elements in the StringCollection.
      StringEnumerator myEnumerator = myCol.GetEnumerator();
      while ( myEnumerator.MoveNext() )
         Console.WriteLine( "{0}", myEnumerator.Current );
      Console.WriteLine();

      // Resets the enumerator and displays the first element again.
      myEnumerator.Reset();
      if ( myEnumerator.MoveNext() )
         Console.WriteLine( "The first element is {0}.", myEnumerator.Current );

   }

}

/*
This code produces the following output.

red
orange
yellow
green
blue
indigo
violet

The first element is red.

*/
Imports System
Imports System.Collections.Specialized

Public Class SamplesStringEnumerator

   Public Shared Sub Main()

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

      ' Enumerates the elements in the StringCollection.
      Dim myEnumerator As StringEnumerator = myCol.GetEnumerator()
      While myEnumerator.MoveNext()
         Console.WriteLine("{0}", myEnumerator.Current)
      End While
      Console.WriteLine()

      ' Resets the enumerator and displays the first element again.
      myEnumerator.Reset()
      If myEnumerator.MoveNext() Then
         Console.WriteLine("The first element is {0}.", myEnumerator.Current)
      End If 

   End Sub 'Main

End Class 'SamplesStringEnumerator 


'This code produces the following output.
'
'red
'orange
'yellow
'green
'blue
'indigo
'violet
'
'The first element is red.

Comentarios

Después de crea un enumerador o después de un Reset es llamado, un enumerador se coloca antes del primer elemento de la colección y la primera llamada a MoveNext desplaza el enumerador hasta el primer elemento de la colección.After an enumerator is created or after a Reset is called, an enumerator is positioned before the first element of the collection, and the first call to MoveNext moves the enumerator over the first element of the collection.

Si MoveNext pasa el final de la colección, el enumerador se coloca después del último elemento de la colección y MoveNext devuelve false.If MoveNext passes the end of the collection, the enumerator is positioned after the last element in the collection and MoveNext returns false. Cuando el enumerador está en esta posición, las llamadas subsiguientes a MoveNext también devolver false hasta Reset se llama.When the enumerator is at this position, subsequent calls to MoveNext also return false until Reset is called.

Un enumerador es válido mientras la colección no cambie.An enumerator remains valid as long as the collection remains unchanged. Si se realizan cambios en la colección, como agregar, modificar, o eliminar elementos, el enumerador queda invalida invalidado y la siguiente llamada a MoveNext o Reset produce una InvalidOperationException.If changes are made to the collection, such as adding, modifying, or deleting elements, the enumerator is irrecoverably invalidated and the next call to MoveNext or Reset throws an InvalidOperationException. Si la colección se modifica entre MoveNext y Current, Current devuelve el elemento que está establecido, incluso si el enumerador ya se ha invalidado.If the collection is modified between MoveNext and Current, Current returns the element that it is set to, even if the enumerator is already invalidated.

Se aplica a

Consulte también: