Question

I’m using the following Powershell script to remove the NumberFormat of the cells in a column for a lot of files so all the fractions will be displayed. The column may have decimal, text or date, etc; only these decimal/currency formatted (with format of 0* or *#*) cells need to be applied

However it’s slow (check/update two or three cells every second). Is there a better/faster way to do it?

    $WorkBook = $Excel.Workbooks.Open($fileName)
    $WorkSheet = $WorkBook.Worksheets.Item(1)
    $cell = $WorkSheet.Cells

    $ColumnIndex = 10 # The column may have decimal, text or date, etc.
    $i = 2

    while ($cell.Item($i, 1).value2 -ne $Null)
      # Replace it to find the last row# of column 1 may cut the time in half? How?
    {
        $c = $cell.Item($i, $ColumnIndex)

        if (($c.NumberFormat -like "0*") -or $c.NumberFormat -like "*#*")
        {
            "$i : $($c.NumberFormat) $($c.value2) "
            $c.NumberFormat = $Null
        }
        $i++
    }

Update:

Will the .Net Microsoft.Office.Interop.Excel much faster?
Or convert the files to xlsx format and use System.IO.Package.IO?

Answer 1

I improved the speed after read the comment. Thanks all.

1. Try to reduce the access of the cells as much as possible. I deleted the output line "$i : $($c.NumberFormat) $($c.value2) " and change

   if (($c.NumberFormat -like "0*") -or $c.NumberFormat -like "*#*")
   to
   $f = $c.NumberFormat
if ($f -like "0*" -or $f -like "*#*")

2. I also use $lastRow = $cell.SpecialCells(11, 1).Row to get the last row number and change the loop to while ($i -le $lastRow).

3. $Excel.ScreenUpdating = False also helped reduced some time.