Loading ...
May 3rd, 2008 by 
Meir Bar-Tal
Sometimes a numbered list is required, such as a list to populate a ListView, TreeView or one to create sequential files in a folder. One of the main problems is that such lists typically sort the items lexicographically, so that numbered items end-up in the wrong order, such as File_1, File_10, FIle_11, …, File_2, FIle_20, etc.
The following function transforms the required number to a string with padding zeroes on the left. This is accomplished by taking the difference between the string lengths of the maximum value in the list and the given number.
'*******************************************************************************
Public Function PadNumber(ByVal intCurrentNum, ByVal intMaxNumInList)
'*******************************************************************************
'Description : Pads a number with zeroes on the left, according to the expected
' maximum length of the numbers in the list.
'
'Purpose : To keep a number list sorted properly, as with a file list (001,
' 002,…, 010, and not 1, 10, 11,…, 2, 20).
'
'Arguments : intCurrentNum (the current number to be padded)
' intMaxNumInList (the top number in the list)
' Note: The arguments are always taken in absolute values
'Returns : The padded intCurrentNum (for example, If 1 and 9999 are sent to
' the function, the result will be 0001)
'
'Developed By : Meir Bar-Tal
'
'Date : 11-Jan-2007
'
'*******************************************************************************
'Validates the arguments - if invalid then it returns the value as is
If (Not IsNumeric(intCurrentNum) Or Not IsNumeric(intMaxNumInList)) Then
PadNumber = intCurrentNum
Exit Function
End If
If (Abs(intCurrentNum) >= Abs(intMaxNumInList)) Then
PadNumber = intCurrentNum
Exit Function
End If
PadNumber = String(len(CStr(Abs(intMaxNumInList)))-len(CStr(Abs(intCurrentNum))), "0″) _
& CStr(Abs(intCurrentNum))
'*******************************************************************************
End Function
'*******************************************************************************
Usage examples:
Msgbox PadNumber(4, 34567) 'Returns 00004
Msgbox PadNumber(-4, 34567) 'Returns 00004
Msgbox PadNumber(4, -34567) 'Returns 00004
Msgbox PadNumber(34567, 4) 'Returns 34567
Msgbox PadNumber(4, 9) 'Returns 4
Msgbox PadNumber("Hello", 9999) 'Returns Hello
You’re invited to customize this function according to your needs.
Posted in Meir Bar-Tal's Blog, VBScript
May 5th, 2008 at 5:22 am
Thanks for the function Meir.
Small correction in the examples, I think you’re missing a zero, eg.
Msgbox PadNumber(4, 34567) ‘Returns 0004
should be
Msgbox PadNumber(4, 34567) ‘Returns 00004
May 5th, 2008 at 7:06 pm
You’re right.
Thanks for the correction, I’ve amended it.