Excel - show which columns are used on any chosen worksheet

[graybags]

yep, 1D array...

[water]

Perfect.
I have modified the function so it works for a 1D array as well:

#include <Excel.au3>

Global $iSheet = 2
; create a Range holding all used cells including unused rows at the top and unused columns on the left
; See: https://www.autoitscript.com/wiki/Excel_Range#Used_Range
With $oWorkbook.Sheets($iSheet)
    $oRangeLast = .UsedRange.SpecialCells($xlCellTypeLastCell)
    $oRange = .Range(.Cells(1, 1), .Cells($oRangeLast.Row, $oRangeLast.Column))
EndWith
; Process the Range
Global $aUsedRange = _Excel_RangeRead($oWorkbook, $iSheet, $oRange)
_ArrayDisplay($aUsedRange)
If UBound($aUsedRange, 0) = 2 Then
    For $iCol = 0 To UBound($aUsedRange, 2) - 1 ; Process all columns
        For $iRow = 0 To UBound($aUsedRange, 1) - 1 ; Process all rows
            If $aUsedRange[$iRow][$iCol] <> "" Then ; add checks for valid columns here
                ; ConsoleWrite(_Excel_ColumnToLetter($iCol + 1) & @CRLF)
                ConsoleWrite($iCol + 1 & @CRLF)
                ExitLoop ; Process next column
            EndIf
        Next
    Next
Else
    For $iRow = 0 To UBound($aUsedRange, 1) - 1 ; Process all rows
        If $aUsedRange[$iRow] <> "" Then ; add checks for valid columns here
            ; ConsoleWrite(_Excel_ColumnToLetter($iCol + 1) & @CRLF)
            ConsoleWrite("A" & @CRLF)
            ExitLoop
        EndIf
    Next
EndIf

If  this works we will add a few lines to create an array with the column names.

[graybags]

That works for a sheet with just one column, great.   Just need to sort the column name array now

[graybags]

I think I've sorted the column name array.  Created an array with:

Local $ColumnInTab[0]

Then:

_ArrayAdd ( $ColumnInTab, _Excel_ColumnToLetter($iCol + 1))

and for the single column:

_ArrayAdd ( $ColumnInTab, "A")

Thanks again for your help, what would I do without this forum!