Prevent a category being displayed when using category="{segment_3_category_id}"

Question

Because of the URL schema on a site I'm working on I'm using {segment_x_category_id} (via Low Seg2Cat - http://gotolow.com/addons/low-seg2cat) to grab the category ID and pass it to a channel entries loop.

The problem I have is that there are a couple of specific categories which I never want to be navigable using this method. Usually I would exclude them specifically using category="not 1|2|3" but when I also need to pass in the category I want to display that's not going to work... any ideas?

Answer 1

@derek's answer is good, except that it will match other categories containing the numbers, like 18.

So, let's improve it using the contains and the concatenation operators, instead of a regex.:

{if '/32/15/8/' *= '/'.segment_x_category_id.'/'}
    {redirect="404"}
{/if}

I'm using / as delimiter, but it could be some different character.

Answer 2

If you're running 2.9, you could use a regular expression conditional to send the visitor to a 404 when trying to browse those categories:

{if segment_x_category_id ~ "/32|15|8/"}
    {redirect="404"}
{/if}

Answer 3

Nathan, you can also check GWcode Categories which gives you more flexibility dealing with categories.

Example:

{exp:gwcode_categories channel="abcd" cat_id="{segment_3_category_id}" depth="1|2" style="linear" excl_cat_id="1|3" limit="9" parse="inward"} {/exp:gwcode_categories}