Wordpress Rewrites - How can I pass a variable to Custom Post Type?

Question

I'm looking for a wordpress rewrite that will let me pass a query var. I have a custom post type that produces urls like this:

example.com/custom-post-slug/custom-post-title/

my goal is to have

example.com/custom-post-slug/custom-post-title/cid/10/

Pass the value 10 into cid

Any suggestions?

Answer 1

You can use add_rewrite_endpoint, which will add a query var and generate the necessary rewrite rules:

function wpd_cid_endpoint() {
    add_rewrite_endpoint( 'cid', EP_PERMALINK );
}
add_action( 'init', 'wpd_cid_endpoint' );

Don't forget to flush rewrite rules after changing rules. You can do this quickly by visiting the Settings > Permalinks page in admin.

Answer 2

You would need to create a custom rewrite rule that maps not just the post slug but also the cid value, see this article:

http://www.prodeveloper.org/create-your-own-rewrite-rules-in-wordpress.html

And the relevant Codex documentation:

http://codex.wordpress.org/Rewrite_API http://codex.wordpress.org/Rewrite_API/add_rewrite_rule

I'm assuming you don't want to use query strings, since in that case it would be as easy as using this URL:

example.com/custom-post-slug/custom-post-title/?cid=10

and getting the value this way:

$cid=isset($_GET['cid'])?$_GET['cid']:false;

However, keep in mind that the .../param_name/param_value/ syntax is not the best in terms of semantics and SEO. URLs are supposed to be hierarchical.

Some use /param_name:param_value/ instead, although the most "pure" solution would be to use ?param_name=param_value.

Answer 3

Try this in your init callback:

add_rewrite_rule(
    '^custom-post-type-slug/([^/]*)/cid/([^/]*)/?',
    'index.php?custom-post-type-slug=$matches[1]&cid=$matches[2]',
    'top'
);

add_rewrite_tag('%cid%', '([^&]+)');

You can then use the following to get your cid variable value:

global $wp_query;
$wp_query->query_vars['cid']

I used the following functions:

http://codex.wordpress.org/Rewrite_API/add_rewrite_rule http://codex.wordpress.org/Rewrite_API/add_rewrite_tag