What are some potential pitfalls to be aware of when generating EAN 13 Barcodes in PHP?

One potential pitfall when generating EAN 13 barcodes in PHP is not properly handling leading zeros in the barcode number. EAN 13 barcodes require a 13-digit number, and if the input number has leading zeros, they must be preserved in the barcode. Failure to do so can result in an invalid barcode. To solve this issue, you can use str_pad() function to ensure the input number is always 13 digits long.

$barcode_number = '0123456789'; // Example barcode number with leading zeros
$barcode_number = str_pad($barcode_number, 13, '0', STR_PAD_LEFT); // Ensure the barcode number is 13 digits long with leading zeros preserved