We're building a site where we're needing to pass a serial number to the cart and only have it show up on the receipt page and receipt email. Ideally I'd like to stay away from making it a hidden field as well in the HTML on the product page in case someone smart enough looks at the source code and grabs it. We're building a site that is selling downloadable products. Upon purchase, they'll be provided a download link and the serial number. Without the serial number, the product will not work.
One thing to note, the user must have a membership before they can go to the checkout, so on this Foxycart forum posting, https://forum.foxycart.com/discussion/5736/i-need-to-pass-a-custom-hidden-field-to-foxycart-so-its-included-in-the-data-feed
, I found someone with a similar question. They were trying to pass hidden values and get it back in the datafeed (if I'm understanding it correctly). So if we can't pass a hidden field to the receipt page, would it be possible to pass hidden information and have it returned in the Foxycart API? If so, we could pass the serial number back via the API to the CMS we're using (MODX) and the user could see the serial number in their membership account.
I don't know if that last part is making it more complicated than need be, but just trying to work through some options.
We're using PHP/Foxycart 2.0/MODX 2.3.3