Only display certain checkout fields if there's a product in the cart from a certain channel

Question

I've got different types of products (in different channels) in a CartThrob store. Is it possible to add a conditional within the Checkout Form tag to enable certain checkout fields to only appear if there's a product from a certain channel in the cart? If so, how would I go about doing this?

I've been looking at the Checkout Form tag and the Cart Items Info tag, but there doesn't appear to be anything here to test for what I'm looking for (please correct me if I'm wrong!). I also looked at the Is In Cart tag, but this only seems to work for adding one entry ID at a time, not looping through lots of entry_id's in a channel (which rules out adding all the entries in this particular channel, though that might have been impractical anyway).

There is a Cart Entry ID's tag, but I can't figure out how to use this in a conditional that would output a single true/false result (for use in a conditional) if one of the pipe-delimited entry ID's belonged to a certain channel. Thanks for any advice on this.

Answer 1

You can probably get this done with stash. This is off the top of my head so please refer to the Stash documentation.

{exp:stash:set name="is_engravable" parse_tags="yes" parse_conditionals="yes" default="0"}{exp:cartthrob:cart_items_info}{if channel_name == "engravable_products"}1{/if}{/exp:cartthrob:cart_items_info}{/exp:stash:set}

{exp:stash:parse process="end"}
  {exp:cartthrob:checkout_form}
  {if {exp:stash:not_empty name="is_engravable"}}
  <label>Engraving</label>
  <input type="text" name="order_engraving">
  {/if}
  {/exp:cartthrob:checkout_form}
{/exp:stash:parse}