Is there a list (of string) or equivalent in VB that I can configure to only hold x entries and then overwrite oldest

Question

Is there a list (of string) or equivalent in VB that I can configure to only hold x entries and then overwrite oldest each time I add something new to it?

e.g. I can set it to hold say 25 items, and then if I add a 26th item it overwrites the first item and so on

Answer 1

HI,
you create your own list class like in following console demo. Add insert item at the top of list.

Module Module64  
  Sub Main()  
    Try  
      Call (New Demo).Execute()  
    Catch ex As Exception  
      Console.WriteLine(ex.ToString)  
    End Try  
    Console.WriteLine("Continue enter key")  
    Console.ReadKey()  
  End Sub  
  
  Friend Class Demo  
    Friend Sub Execute()  
      Dim itemList As New MyList(Of String)(5)  
      For i = 1 To 7  
        itemList.Add($"Item {i}")  
      Next  
      For Each item In itemList  
        Console.WriteLine(item)  
      Next  
    End Sub  
  End Class  
  
  Friend Class MyList(Of T)  
    Inherits List(Of T)  
  
    Private _maxCount As Integer  
    Public Sub New(maxCount As Integer)  
      Me._maxCount = maxCount  
    End Sub  
  
    Friend Shadows Sub Add(item As T)  
      Me.Insert(0, item)  
      If Me.Count > Me._maxCount Then Me.RemoveAt(Me.Count - 1)  
    End Sub  
  End Class  
  
End Module  

Result:

Answer 2

Answer moved to later in this tread.

Answer 3

@Dewayne Basnett

Thanks for that

As an amendment to my original question, is the below possible:-

Basically the list (of string) will hold historical related information - so would be handy if the list could be reversed e.g. newest item gets added to top (rather than bottom) of the list, and oldest gets removed from the bottom of the list (rather than top), so when I then output it to wherever it would appear in correct order - hope this makes sense

Answer 4

I thought that was quite clear from my post... but reversing the current order, as at the moment anything new you add goes to bottom of list and the top oldest one is removed, wheras ideally (but not essential, was just asking if possible) I want to add new to TOP of list and removed the old one from BOTTOM

So if we added 1, 2, 3, 4, 5 then it would be stored as 5, 4, 3, 2,1 as oldest at bottom, newest at top

Answer 5

anonymous user-3316

Perfect - thanks