I need to be able to convert any string into a code128 barcode that can be printed on a PDF.
My idea was to embed a code128 font into the PDF and simply use that font to render the string that I need to show as a barcode, letter for letter.
However, I found out that I also need to calculate a checksum and include the start and stop characters.
Is this not possible using PHP? I have not found any solution anywhere. The only solutions that I could find are for directly rendering the barcode as an image, which does not help in my current situation, since I need to use a font to create the barcode in the PDF.
The easisest way to generate a barcode in PHP for PDF is to use a dedicated software library.
AFAIK, the most complete one is currently the tc-lib-barcode (https://github.com/tecnickcom/tc-lib-barcode) that allows you to generate both linear and bidimensional barcodes. The included example should give you a quick start.
The source code is fully PSR-2 compliant and can be easily added to your PHP projects using Composer.
The original code has been ported and refactored from TCPDF and already used in billions of documents.