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Quicksort for multiple columns in excel vba userform

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Last Modified: 2008-01-09
I have a multicolumn listbox that I want to have the option of sorting any of the 7 columns. I would use the bubblesort, but there can be potentially 35000 in the list which makes it kind of slow. I found the code below for quicksort, but I am not sure how I can modify it so that I can sort multiple columns, not just one. Can anyone help me?

Sub Quicksort (List() As Long, min As Integer, max As Integer)
Dim med_value As Long
Dim hi As Integer
Dim lo As Integer
Dim i As Integer

    ' If the list has no more than 1 element, it's sorted.
    If min >= max Then Exit Sub

    ' Pick a dividing item.
    i = Int((max - min + 1) * Rnd + min)
    med_value = List(i)

    ' Swap it to the front so we can find it easily.
    List(i) = List(min)

    ' Move the items smaller than this into the left
    ' half of the list. Move the others into the right.
    lo = min
    hi = max
    Do
        ' Look down from hi for a value < med_value.
        Do While List(hi) >= med_value
            hi = hi - 1
            If hi <= lo Then Exit Do
        Loop
        If hi <= lo Then
            List(lo) = med_value
            Exit Do
        End If

        ' Swap the lo and hi values.
        List(lo) = List(hi)
       
        ' Look up from lo for a value >= med_value.
        lo = lo + 1
        Do While List(lo) < med_value
            lo = lo + 1
            If lo >= hi Then Exit Do
        Loop
        If lo >= hi Then
            lo = hi
            List(hi) = med_value
            Exit Do
        End If

        ' Swap the lo and hi values.
        List(hi) = List(lo)
    Loop

    ' Sort the two sublists
    Quicksort List(), min, lo - 1
    Quicksort List(), lo + 1, max
End Sub
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