MoveNext Método
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IEnumerator.MoveNext (Método) ()

 

Desplaza el enumerador al siguiente elemento de la colección.

Espacio de nombres:   System.Collections
Ensamblado:  mscorlib (en mscorlib.dll)

bool MoveNext()

Valor devuelto

Type: System.Boolean

Es true si el enumerador avanzó con éxito hasta el siguiente elemento; es false si el enumerador alcanzó el final de la colección.

Exception Condition
InvalidOperationException

The collection was modified after the enumerator was created.

After an enumerator is created or after the Reset method is called, an enumerator is positioned before the first element of the collection, and the first call to the MoveNext method moves the enumerator over the first element of the collection.

If MoveNext passes the end of the collection, the enumerator is positioned after the last element in the collection and MoveNext returns false.When the enumerator is at this position, subsequent calls to MoveNext also return false until Reset is called.

An enumerator remains valid as long as the collection remains unchanged.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.

The following code example demonstrates the implementation of the IEnumerator interfaces for a custom collection.In this example, MoveNext is not explicitly called, but it is implemented to support the use of foreach (for each in Visual Basic).This code example is part of a larger example for the IEnumerator interface.

// When you implement IEnumerable, you must also implement IEnumerator.
public class PeopleEnum : IEnumerator
{
    public Person[] _people;

    // Enumerators are positioned before the first element
    // until the first MoveNext() call.
    int position = -1;

    public PeopleEnum(Person[] list)
    {
        _people = list;
    }

    public bool MoveNext()
    {
        position++;
        return (position < _people.Length);
    }

    public void Reset()
    {
        position = -1;
    }

    object IEnumerator.Current
    {
        get
        {
            return Current;
        }
    }

    public Person Current
    {
        get
        {
            try
            {
                return _people[position];
            }
            catch (IndexOutOfRangeException)
            {
                throw new InvalidOperationException();
            }
        }
    }
}

Universal Windows Platform
Disponible desde 4.5
.NET Framework
Disponible desde 1.1
Portable Class Library
Compatible con: portable .NET platforms
Silverlight
Disponible desde 2.0
Windows Phone Silverlight
Disponible desde 7.0
Windows Phone
Disponible desde 8.1
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