Technically, bar code fonts when they are built correctly are seen as any other font. They should export to PDF just fine. HTML is another story.
well, a QRCode won’t work with a font.
Michel if one was to manually calculate the checksum digit for upc-a would it work the same?
Checksum is not the worst part. Assembling a barcode will require assembling bars with calculus as well, with a set of bar for even result, and another for uneven. Look at the Wikipedia page I linked to.