Remove add_to_cart_form button after a fixed quantity of a certain product added to cart

Question

I need to be able to limit how many of a certain product can be added to the cart.

I thought I could use {cart_items_info} with an {entry_id} parameter to limit to the product I'm targeting and then use a conditional based on {total_items}, e.g.

{exp:cartthrob:cart_items_info entry_id="XXX"}
{total_items} {!-- returns the total of other items in the cart too, not just the entry_id specified --}
{if total_items <=5} … {/if}
{/exp:cartthrob:cart_items_info}

but the tag seems to return the whole cart total items regardless of whether I use the entry_id param or not.

Is this a bug with cart_items_info or is there another way I should be going about this?

Answer 1

We had a scenario where free samples are offered by the client, but they only wanted customers to be able to request 1 sample pack at a time to discourage people buying the cheaper samples instead of the real product.

On the product page we have the following:

<div class="add-to-basket">
  {if {exp:cartthrob:is_in_cart entry_id="249"}}
  <p>It looks like you've already added samples to your basket. Our sample packs are free (subject to postage) so they are limited to one per customer.</p>
  {if:else}
  <button type="submit">Add To Basket</button>
  {/if}
</div>

The difference here is we didn't need to count the products as they were limited to just 1. Not sure whether you could use another conditional within {if {exp:cartthrob:is_in_cart entry_id="xxx"}}?