Option Explicit

  Function Azalea_GS1_128_C(ByVal yourData As String) As String
    ' C128Tools v6.0 24apr07 rev 001 jwhiting
    ' Copyright 2007 Azalea Software, Inc. All rights reserved. www.azalea.com
    ' yourData is a string to be encoded as a GS1-128 code set C symbol.
    ' yourData must be an even number of digits long. If not, pad it with a leading zero first.
    ' Format the output, Azalea_GS1_128_C, using one of Azalea Software's Code 128 barcode fonts.

    Dim fontString As String                ' encoded data
    Dim temp As String                      ' throwaway variable
    Dim checkDigitSubtotal As Integer       ' weighted subtotal
    Dim chunk As String                     ' loop variable
    Dim i As Integer                        ' just a counter
    
    ' seed the variables
    fontString = Chr(183) & Chr(205)        ' code set C start & FNC1 glyphs
    checkDigitSubtotal = 207                ' code set C start & FNC1 checkdigit values (105 + 102 = 207)
    temp = yourData                         ' 2 character chunks

    ' pad odd length input with a leading zero goesHereLater
    
    ' first do the mod 103 check digit calculation
    ' then map into the Azalea Code 128 character set
    For i = 1 To Len(yourData) / 2
      chunk = Left$(temp, 2)
      checkDigitSubtotal = checkDigitSubtotal + Val(chunk) * (i + 1)
      Select Case Val(chunk)
        Case 0
          fontString = fontString + Chr(206)
        Case 1 To 93
          fontString = fontString & Chr(Val(chunk) + 32)
        Case Is > 93
          fontString = fontString & Chr(Val(chunk) + 103)
      End Select
      temp = Right$(temp, Len(temp) - 2)
    Next i
    checkDigitSubtotal = checkDigitSubtotal Mod 103

    ' build the output string
    ' code set C start bar, the encoded string, check digit, stop bar
    Select Case checkDigitSubtotal
      Case 0
        Azalea_GS1_128_C = fontString & Chr(194) & Chr(196)
      Case 1 To 93
        Azalea_GS1_128_C = fontString & Chr(checkDigitSubtotal + 32) & Chr(196)
      Case Is > 93
        Azalea_GS1_128_C = fontString & Chr(checkDigitSubtotal + 103) & Chr(196)
    End Select
End Function