Compare Two Custom Post Types Using The Same Custom Taxonomy

Question

I have two post types, courses and testimonials, sharing the same taxonomies. What I am looking to accomplish is to check whether a course is in the same category as a testimonial. Then display if it is, keeping in mind they could have more than one category each.

I am currently able to check which categories they are in using get_the_term_list() but can't figure out how to go about comparing them to one another.

What I need is to be able to check is if the categories checked off in pm_course(post-type) is the same as course_testimonials(post-type). If they have the same category then I want to display the testimonial, if not I want to do nothing.

Really a basic if else statement but I can't seem to find a way to see if the checked categories are the same in both.

Answer 1

Don't use get_the_term_list() as it returns an HTML string, which makes comparing more difficult.

Use wp_get_post_terms() (Codex link) instead. It can return an array, and then you can use something like array_intersect() to get the terms that match.

Your code should look something like this (I haven't tested this):

$course_terms = wp_get_post_terms($course_post_id, 'course_type'. array('fields'=>'slug'));
$testimonial_terms = wp_get_post_terms($testimonial_post_id, 'course_type'. array('fields'=>'slug')); 
$matches = array_intersect($course_terms, $testimonial_terms);
if (count($matches) > 0) echo "matching terms";