StringEnumerator.MoveNext Method ()

 
System_CAPS_noteNote

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Advances the enumerator to the next element of the collection.

Namespace:   System.Collections.Specialized
Assembly:  System (in System.dll)

Public Function MoveNext As Boolean

Return Value

Type: System.Boolean

true if the enumerator was successfully advanced to the next element; false if the enumerator has passed the end of the collection.

Exception Condition
InvalidOperationException

The collection was modified after the enumerator was created.

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.

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. 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.

The following code example demonstrates several of the properties and methods of StringEnumerator.

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.

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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