how to get category`s slug in WP_Query loop?

Question

i use below code :

//custom post = project
//taxonomy = project-category

$args = array(
    'post_type' => 'project',
);
$query = new WP_Query( $args );

// The Loop
if ( $query->have_posts() ) {
    while ( $query->have_posts() ) {
         $query->the_post(); ?>

             <div class="element-item col-lg-4 project hover-trigger landscape transition motal" data-category="transition"></div>

             <?php
          }
    wp_reset_postdata();
 }

how to get category`s slug of each post in loop?

Thanks

Answer 1

get_the_category() retrieves WP_Term objects for all the categories assigned to the post. You can combine that with wp_list_pluck() to just get the slugs:

$categories = get_the_terms( null, 'project-category' );
$category_slugs = wp_list_pluck( $categories, 'slug' );

$category_slugs will now be an array of slugs for the categories of the post.