[RESOLVED] [2005] Advanced String Manipulation

[GedOfEarthsea]

Now I am having troubles deleting duplicate lines for some reason.

I got this code for erasing duplicate lines, but it isn't working when I try modifying it for this application:

Dim Lines As New ArrayList
        'put all the lines of the textfile into the arraylist
        Lines.AddRange(IO.File.ReadAllLines("C:\dns.txt"))
        'loop the arraylist in reverse because the IndexOf searches top to bottom
        For i As Integer = Lines.Count - 1 To 0 Step -1
            'if the return index is smaller than the index of the line we are
            'searching for then we can remove that line because there is a duplicate
            If Lines.IndexOf(Lines(i)) < i Then
                Lines.RemoveAt(i)
            End If
        Next