VBA Difference between FieldInfo and .NumberFormat = "@"

Question

I've got a program extracting me data under.XLS format it gives me something like that:

Then, I run a macro:

Dim file As String
Const r_as400 = "C:\test\"
Const r_colos = "C:\test\save\"
Const file_name= "TCODES_PRODUITS.xls"

Sub test()
'
' test Macro
'

'
    file= r_as400 & file_name

    Workbooks.OpenText Filename:=file, Origin:=xlMSDOS, StartRow:=1, _
        DataType:=xlDelimited, TextQualifier:=xlDoubleQuote, ConsecutiveDelimiter:=False, _
        Tab:=True, Semicolon:=False, Comma:=False, Space:=False, Other:=False, _
        FieldInfo:=Array(Array(1, 2), Array(2, 1), Array(3, 1), Array(4, 2), Array(5, 1), _
        Array(6, 1), Array(7, 1), Array(8, 1), Array(9, 1), Array(10, 1), Array(11, 1), _
        Array(12, 1), Array(13, 1), Array(14, 1), Array(15, 1), Array(16, 1), Array(17, 1), _
        Array(18, 1)), TrailingMinusNumbers:=True

After that my file is looking like this:

As you can see, in the first screen there is rows with only 1 digit and others with 13

After the macro, some row are equal to others to

I'd tried something, from the initial file I changed column D format into text (NumberFormat ('@')) but it doesn't change anything.

Someone can explain to me difference and how the VBA instruction know how much "0" must be present before "1"?

Answer 1

Please, try the next code. Of course, your used constants must exist as they are:

Sub testCreateNecessaryLeadingZeros()
  Dim wb As Workbook, ws As Worksheet, lastR As Long, rng As Range, arr, i As Long
  
  Set wb = Workbooks.Open(r_as400 & file_name)
   Set ws = wb.Sheets(1)
   lastR = ws.Range("D" & ws.rows.count).End(xlUp).row 'last row on D:D
   Set rng = ws.Range("D2:D" & lastR)
   arr = rng.value 'place it in an array
    For i = 1 To UBound(arr)
        arr(i, 1) = Format(arr(i, 1), "00000000000000")
   Next
   rng.NumberFormat = "@"  'format the range as text
   rng.value = arr         'drop the array content, at once
End Sub