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How to use IEnumerator.Res et with generic collection in VB.NET

From the documentation in MSDN, it looks as though the following should
iterate through the collection twice. However, MoveNext in the second
iteration returns false:
Dim oList As New List(Of String)
oList.Add("Hell o")
oList.Add("worl d")
Dim oEnum As List(Of String).Enumera tor = oList.GetEnumer ator()
While oEnum.MoveNext( )
Dim sValue As String = oEnum.Current
End While
CType(oEnum, IEnumerator).Re set()
While oEnum.MoveNext( )
Dim sValue As String = oEnum.Current
End While
Anyone know what I am doing wrong?
May 4 '06 #1
2 5135
"wvtempl" <wv*****@discus sions.microsoft .com> wrote in message
news:DF******** *************** ***********@mic rosoft.com...
From the documentation in MSDN, it looks as though the following should
iterate through the collection twice. However, MoveNext in the second
iteration returns false:
Dim oList As New List(Of String)
oList.Add("Hell o")
oList.Add("worl d")
Dim oEnum As List(Of String).Enumera tor = oList.GetEnumer ator()
While oEnum.MoveNext( )
Dim sValue As String = oEnum.Current
End While
CType(oEnum, IEnumerator).Re set() Try oEnum = oList.GetEnumer ator() instead to start over with a brand new
enumerator.
Or just use For Each and let the compiler take care of the enumerators. While oEnum.MoveNext( )
Dim sValue As String = oEnum.Current
End While
Anyone know what I am doing wrong?

May 4 '06 #2
Thanks, getting a new enumerator is the workaround I have been using. Does
anyone know if the Reset method simply doesn't work, or if the way I am
calling it is incorrect?

"Ben Voigt" wrote:
"wvtempl" <wv*****@discus sions.microsoft .com> wrote in message
news:DF******** *************** ***********@mic rosoft.com...
From the documentation in MSDN, it looks as though the following should
iterate through the collection twice. However, MoveNext in the second
iteration returns false:
Dim oList As New List(Of String)
oList.Add("Hell o")
oList.Add("worl d")
Dim oEnum As List(Of String).Enumera tor = oList.GetEnumer ator()
While oEnum.MoveNext( )
Dim sValue As String = oEnum.Current
End While
CType(oEnum, IEnumerator).Re set()

Try oEnum = oList.GetEnumer ator() instead to start over with a brand new
enumerator.
Or just use For Each and let the compiler take care of the enumerators.
While oEnum.MoveNext( )
Dim sValue As String = oEnum.Current
End While
Anyone know what I am doing wrong?


May 4 '06 #3

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