I am using a CPT (post_type => 'portfolio_type', taxonomy => 'portfolio_cat'). Under this CPT, I have design, web development category. I am trying to get the post with the category. My best try,

function callback_for_portfolio_shortcode(){
    $args['tax_query'] = array(
        array(
            'taxonomy' => 'portfolio',
            'field' => 'id',
            'terms' => $parent_cat
        )
    );
    $query = new WP_Query($args);
    if ($query->have_posts()) :
        while ($query->have_posts()): $query->the_post();
            $post_id = get_the_ID();
            $post_categories = wp_get_post_categories( $post_id );
            $cat_str = '';

            //loop through the category and get a string of category
            foreach($post_categories as $c){
                $cat = get_category( $c );
                $cat_str .= $cat->name;
            }
            $html .= '<h4>'.$query->post->post_title.'</h4>'; //works fine 
            $html .= '<h4>'.substr(get_field('job_description', $id), 0, 100).'</h4>'; //works fine 
            $html .= '<h4>'.post_permalink().'</h4>'; //works fine 
            $html .= '<h4>'.$cat_str.'</h4>'; //does not work    
        endwhile;
    endif;
    return $html;
}

$cat_str is empty. What am I missing here? Thanks.

I am using a CPT (post_type => 'portfolio_type', taxonomy => 'portfolio_cat'). Under this CPT, I have design, web development category. I am trying to get the post with the category. My best try,

function callback_for_portfolio_shortcode(){
    $args['tax_query'] = array(
        array(
            'taxonomy' => 'portfolio',
            'field' => 'id',
            'terms' => $parent_cat
        )
    );
    $query = new WP_Query($args);
    if ($query->have_posts()) :
        while ($query->have_posts()): $query->the_post();
            $post_id = get_the_ID();
            $post_categories = wp_get_post_categories( $post_id );
            $cat_str = '';

            //loop through the category and get a string of category
            foreach($post_categories as $c){
                $cat = get_category( $c );
                $cat_str .= $cat->name;
            }
            $html .= '<h4>'.$query->post->post_title.'</h4>'; //works fine 
            $html .= '<h4>'.substr(get_field('job_description', $id), 0, 100).'</h4>'; //works fine 
            $html .= '<h4>'.post_permalink().'</h4>'; //works fine 
            $html .= '<h4>'.$cat_str.'</h4>'; //does not work    
        endwhile;
    endif;
    return $html;
}

$cat_str is empty. What am I missing here? Thanks.

• custom-post-types
• shortcode
• categories

• You use the wrong operator to concatenate strings, you should replace it with .=. $cat_str .= $cat->name; – nmr Commented Apr 5, 2019 at 7:04
• just a typo mistake. sorry! – Abdullah Raihan Bhuiyan Commented Apr 5, 2019 at 7:54

1 Answer 1

wp_get_post_categories() and get_category() are specifically for the category taxonomy. You're using a custom taxonomy, portfolio_cat, so you need to use get_the_terms() to get categories.

$categories = get_the_terms( $post_id, 'portfolio_cat' );
$cat_str    = '';

foreach ( $post_categories as $category ) {
    $cat_str .= $category->name;
}

If you just want a comma separated list of category links, you can use get_the_term_list() to simplify the code:

$cat_str = get_the_term_list( $post_id, 'portfolio_cat', '', ', ', '' );

Or, if you don't want links, you can do this instead:

$categories = get_the_terms( $post_id, 'portfolio_cat' );
$cat_str    = implode( ', ', wp_list_pluck( $categories, 'name' ) );

Also, instead of $query->post->post_title you should really just be using get_the_title();.