This is a really good example! Instead of re-declaring an array for each row, you just add new value (s) to array list, then at the end you convert array list to the desired array. That's true, it is easier this way and I think more elegant! Thanks!
On Feb 3, 10:11 am, rbdavidson <[email protected]> wrote: > Here's a function I use in a real world app with both. > Public Function GetAllowableValues(ByVal IncludeDescription As > Boolean) As String() > Dim Retval As New ArrayList > > For Each row As DataRow In Data.Rows > If IncludeDescription Then > Retval.Add(row(ReturnColumn).ToString & " - " & row > (DescriptionColumn).ToString) > Else > Retval.Add(row(ReturnColumn)) > End If > Next > Return CType(Retval.ToArray(GetType(String)), String()) > End Function > > The For Each uses enumeration to loop over the all the rows in a > DataTable. I add the appropriate string to an ArrayList. At the end > I convert the ArrayList to an array of string and return the list of > allowable values. I could have declared a fixed array of String > (which would honestly be more efficient), or used some other > collection, but ArrayList was just so darn easy to use I couldn't > resist it. > > After filling the ArrayList itself, I could have used a "For Each > value as String In Retval" to enumerate over the data in RetVal and do > whatever processing I need to on the strings. > > - R.B.Davidson > > On Feb 2, 12:00 pm, john <[email protected]> wrote: > > > Hi there, > > > I was yesterday reviewing and re-reading my books, and came up with > > this question. > > I understand concept of enumeration and arraylist in .NET, but can > > somebody provide me with a real business example of both enumeration > > and arraylist? I was trying to find something on the web, but all the > > examples that I was able to find so far were very basic, just to > > explain the idea of each concept.
