EAN128 barcodes in Excel

EAN128 barcodes in Excel

Source:	DataSource
Language:	English
Topic:	Microsoft
SubTopic:	Excel
Last Edit By:	DochyJP
LastEdit:	2021-11-24
Document type:	Documentation
Status:	Active
Access:	free

Easily generate Code 128 barcodes in Excel

A Code 128 barcode has six sections:

1. Quiet zone
2. Start character
3. Encoded data
4. Check character
5. Stop character
6. Quiet zone

The check character is calculated from a weighted sum (modulo 103) of all the characters. Because of this, the generation of Code 128 barcodes is not as simple as typing the number sequence into a programme using a barcode font. Attempting to do this with Code 128 barcodes will fail.

Step 1

Download the Code 128 barcode font and install in your fonts folder at c:\windows\fonts. (You will need administrator permissions to do this). Without being administrator, you can just drag & drop the ttf file from Font management under Windows.

Step 2

Ensure that you have the Developer module enabled in Excel.

Step 3

Create a new Microsoft Excel sheet. Create a table (making sure that you ‘format as table‘) with the following structure and headings:

Caption text

Barcode	Barcode String	Barcode Presentation	Check
X	X	X	X

Step 4

In Excel, go to the Developer ribbon and choose “Visual Basic”.

Step 5

Right-click on “Modules” in the tree on the left and select “Insert Module”. Then paste the following code :

Option Explicit
Public Function Code128(SourceString As String)
    'Written by Philip Treacy, Feb 2014
    'http://www.myonlinetraininghub.com/create-barcodes-with-excel-vba
    'This code is not guaranteed to be error free.  No warranty is implied or expressed. Use at your own risk and carry out your own testing
    'This function is governed by the GNU Lesser General Public License (GNU LGPL) Ver 3
    'Input Parameters : A string
    'Return : 1. An encoded string which produces a bar code when dispayed using the CODE128.TTF font
    '         2. An empty string if the input parameter contains invalid characters
    Dim Counter As Integer
    Dim CheckSum As Long
    Dim mini As Integer
    Dim dummy As Integer
    Dim UseTableB As Boolean
    Dim Code128_Barcode As String
    If Len(SourceString) > 0 Then
        'Check for valid characters
        For Counter = 1 To Len(SourceString)
            Select Case Asc(Mid(SourceString, Counter, 1))
                Case 32 To 126, 203
                Case Else
                    MsgBox "Invalid character in barcode string." & vbCrLf & vbCrLf & "Please only use standard ASCII characters", vbCritical
                    Code128 = ""
                    Exit Function
            End Select
        Next
        Code128_Barcode = ""
        UseTableB = True
        Counter = 1
        Do While Counter <= Len(SourceString)
            If UseTableB Then
                'Check if we can switch to Table C
                mini = IIf(Counter = 1 Or Counter + 3 = Len(SourceString), 4, 6)
                GoSub testnum
                If mini% < 0 Then 'Use Table C
                    If Counter = 1 Then
                        Code128_Barcode = Chr(205)
                    Else 'Switch to table C
                        Code128_Barcode = Code128_Barcode & Chr(199)
                    End If
                    UseTableB = False
                Else
                    If Counter = 1 Then Code128_Barcode = Chr(204) 'Starting with table B
                End If
            End If
            If Not UseTableB Then
                'We are using Table C, try to process 2 digits
                mini% = 2
                GoSub testnum
                If mini% < 0 Then 'OK for 2 digits, process it
                    dummy% = Val(Mid(SourceString, Counter, 2))
                    dummy% = IIf(dummy% < 95, dummy% + 32, dummy% + 100)
                    Code128_Barcode = Code128_Barcode & Chr(dummy%)
                    Counter = Counter + 2
                Else 'We haven't got 2 digits, switch to Table B
                    Code128_Barcode = Code128_Barcode & Chr(200)
                    UseTableB = True
                End If
            End If
            If UseTableB Then
                'Process 1 digit with table B
                Code128_Barcode = Code128_Barcode & Mid(SourceString, Counter, 1)
                Counter = Counter + 1
            End If
        Loop
        'Calculation of the checksum
        For Counter = 1 To Len(Code128_Barcode)
            dummy% = Asc(Mid(Code128_Barcode, Counter, 1))
            dummy% = IIf(dummy% < 127, dummy% - 32, dummy% - 100)
            If Counter = 1 Then CheckSum& = dummy%
            CheckSum& = (CheckSum& + (Counter - 1) * dummy%) Mod 103
        Next
        'Calculation of the checksum ASCII code
        CheckSum& = IIf(CheckSum& < 95, CheckSum& + 32, CheckSum& + 100)
        'Add the checksum and the STOP
        Code128_Barcode = Code128_Barcode & Chr(CheckSum&) & Chr$(206)
    End If
    Code128 = Code128_Barcode
    Exit Function
testnum:
        'if the mini% characters from Counter are numeric, then mini%=0
        mini% = mini% - 1
        If Counter + mini% <= Len(SourceString) Then
            Do While mini% >= 0
                If Asc(Mid(SourceString, Counter + mini%, 1)) < 48 Or Asc(Mid(SourceString, Counter + mini%, 1)) > 57 Then Exit Do
                mini% = mini% - 1
            Loop
        End If
        Return
End Function

Step 6

Go back to your Excel sheet and insert the following formulae:

• In cell B2 (“Barcode String”), insert =Code128([@Barcode])
• In cell C2 (“Barcode Presentation”), insert =[@[Barcode String]]
• In cell D2 (“Check”), insert: =IF(ISNUMBER(SEARCH("Â",[@[Barcode Presentation]],1)),"Error!","")

The formulae should copy down the entire columns. Save your sheet. Attention, this require an xlsm file format.

Step 7

Highlight Column C and change the font to “Code 128”. Now when you enter data into cell A2, a barcode should be displayed in cell C2 and so-on down the entire sheet.

If this doesn’t work, you may need to close and re-open Excel at this stage.