Hidde certain category from post meta

Question

This is my code for showing categories on post meta:

$categories_list = get_the_category_list(  ', ', 'ixn' );
printf( '<span class="cat-links">' . ( 'Category: %1$s', 'ixn' ) . '</span>', $categories_list ); 

('ixn' is the theme name)

Is there a simple way to hide a specific category, called "site" from the categories that appear on the post meta?

I have read these supposed solutions, but they may be overkill for what I need and don't fit well with my code as they don't use the get_the_category_list:

• Hide a certain category name without removing it?
• https://rockingwplikeapro.com/hide-category-names-from-display-in-wordpress-theme/
• https://www.webhostinghero.com/exclude-specific-categories-from-the-meta-info-in-wordpress/

Answer 1

From quick look through related functions I don't think there is one that retrieves terms for the post and allows explicit exclusion.

However there is a convenient filter the_category_list right inside the function you use, with array of category objects, before they are turned into HTML output.

This should be a very fitting place to check the array and exclude the category you wish to skip. As always take care to only add your filter within required context or check for context within it.

Answer 2

This is the code that worked. Although it hooks on the_category and not on the the_category_list or get_the_categoty_list it works flawlessly.

function the_category_filter($thelist,$separator=' ') {
    if(!defined('WP_ADMIN')) {
        //list the category names to exclude
        $exclude = array('Mac','Windows');
        $cats = explode($separator,$thelist);
        $newlist = array();
        foreach($cats as $cat) {
            $catname = trim(strip_tags($cat));
            if(!in_array($catname,$exclude))
                $newlist[] = $cat;
        }
        return implode($separator,$newlist);
    } else
        return $thelist;
}
add_filter('the_category','the_category_filter',10,2);

If you want to limit this exclusion only in single posts you can enclose the code in an if statement like this:

if ( is_single() ) {
// Above code goes here
}

PS: I still wonder if there is an finer solution. For example by using something like: get_the_categories_list('exclude=1,22') in my code.