Function Azalea_UPC_A(ByVal UPCnumber As String) As String
' UPCTools 16may12 jwhiting
' Copyright 2012 Azalea Software, Inc. All rights reserved. www.azaleabarcodes.com

' Creating a UPC version A in Excel
' Your input, UPCnumber, is a string consisting of an 11-, 12-, or 14-digit number.
' company prefix + product ID, company prefix + product ID + check digit, or GTIN (Global Trade Identification Number)
  
  Dim checkDigitSubtotal As Integer  ' a check digit throwaway
  Dim i As Integer                   ' our loop counter
  Dim checkDigit As String           ' the check digit itself
  Dim temp As String                 ' a temporary placeholder
  
  ' Possible valid input includes 11-digits (no check digit), 12-digits (with check digit), or 14-digits (GTIN).
  Select Case Len(UPCnumber)
    Case 11
      ' We're going to do the UPC check digit calculation because the input doesn't have it.
    Case 12
      ' Let's strip your check digit and calculate it from scratch.
       UPCnumber = Left(UPCnumber, 11)
   Case 14
      ' GTIN input, but we're going to strip the leading 2 and the last characters to extract the 11-digit input without check digit.
      UPCnumber = Mid(UPCnumber, 3, 11)
   Case Else
      ' Your error handling goes here...
   End Select
    
  ' Build the output string beginning with the first human-readable digit, a spacer, the left guard bars, and the bars for the first character.
  Select Case Left(UPCnumber, 1)
    Case "0"
      temp = "U|xa"
    Case "1"
      temp = "[|xb"
    Case "2"
      temp = "V|xc"
    Case "3"
      temp = "W|xd"
    Case "4"
      temp = "X|xe"
    Case "5"
      temp = "Y|xf"
    Case "6"
      temp = "Z|xg"
    Case "7"
      temp = "u|xh"
    Case "8"
      temp = "\|xi"
    Case "9"
      temp = "]|xj"
  End Select
  
  ' Continue with the 5 numbers in the left notch.
  For i = 2 To 6 Step 1
    temp = temp + Chr(65 + (Val(Mid(UPCnumber, i, 1))))
  Next i
  
  ' Now we need to do the UPC A check digit calculation.
  ' Add up the numbers in the odd positions left to right. Multiple the result by 3.
  ' Add up the numbers in the even positions. Now add the first subtotal to the second.
  ' The UPC barcode check digit is the single digit number makes the total a multiple of 10.
checkDigitSubtotal = (Val(Left(UPCnumber, 1))) + (Val(Mid(UPCnumber, 3, 1))) + (Val(Mid(UPCnumber, 5, 1))) + (Val(Mid(UPCnumber, 7, 1))) + (Val(Mid(UPCnumber, 9, 1))) + (Val(Right(UPCnumber, 1)))
checkDigitSubtotal = (3 * checkDigitSubtotal) + (Val(Mid(UPCnumber, 2, 1))) + (Val(Mid(UPCnumber, 4, 1))) + (Val(Mid(UPCnumber, 6, 1))) + (Val(Mid(UPCnumber, 8, 1))) + (Val(Mid(UPCnumber, 10, 1)))
checkDigit = Right(Str(300 - checkDigitSubtotal), 1)

  ' Continue to build the output string by adding the center guard bars, 5 digits in the right notch, check digit and right guard bars.
  temp = temp + "y" + Right(UPCnumber, 5) + Chr(107 + (Val(checkDigit))) + "z"
  
  ' Lastly let's add the human readable for the check digit in the lower right corner.
  Select Case checkDigit
    Case "0"
      Azalea_UPC_A = temp + "U"
    Case "1"
      Azalea_UPC_A = temp + "["
    Case "2"
      Azalea_UPC_A = temp + "V"
    Case "3"
      Azalea_UPC_A = temp + "W"
    Case "4"
      Azalea_UPC_A = temp + "X"
    Case "5"
      Azalea_UPC_A = temp + "Y"
    Case "6"
      Azalea_UPC_A = temp + "Z"
    Case "7"
      Azalea_UPC_A = temp + "u"
    Case "8"
      Azalea_UPC_A = temp + "\"
    Case "9"
      Azalea_UPC_A = temp + "]"
  End Select
  
  ' The output, Azalea_UPC_A, needs to be formatted in one of Azalea Software's UPC fonts.
  ' We recommend UPCTallThin at 73 points.

  ' Excel: B1=Azalea_UPC_A(A1)
  ' Or put another way, yourContainer.text=Azalea_UPC_A(yourInputString)
  
End Function