Append taxonomy terms as class names in markup?

Question

I've defined a custom post type for "person", and I'd like to append class names to the output markup based on taxonomies that correspond to team names. For example, if a person is part of the "creative" and "interactive" teams, I'd like to output the following:

<div class="person creative interactive">Jane</div>

I found this thread on the forum, but in my case I need to output the taxonomy names within an echo statement, as the output is defined as a function in my functions.php file.

Here is a reduced version of what I've come up with so far, based on the aforementioned thread and this Stack Overflow thread:

function display_all_people() {
    // set up arguments for new post query
    $args = array(
        'post_type' => 'people',
        'order' => 'ASC',
        'orderby'    => 'meta_value',
        'meta_key'   => 'last_name'
        );

    $peoplePosts = new WP_Query( $args );
    if ( $peoplePosts->have_posts() ) {
        echo '<div class="people-listing">';
        while ( $peoplePosts->have_posts() ) {
            $peoplePosts->the_post();
            $terms = get_the_terms( $post->ID, 'teams' );

            foreach ($terms as $term) {
                echo '<div class="person' . implode('', $term->slug) . '">';
            }

            echo '<div>More markup for each person listing</div>';
            echo '</div>';
        } 
        echo '</div>';
    } else {
        return '<p>Nothing Here.</p>';
    }
    wp_reset_postdata();
}

Thus, I'm trying to use the implode() to concatenate the values of the array (i.e. "team" taxonomy names), but it doesn't seem to be working (PHP is throwing errors.) Any idea how I can successfully append the taxonomies as class names in this way? Thanks for any assistance here.

Answer 1

Differ the output until you have a collection ready.

$terms = get_the_terms( $post->ID, 'teams' );

// create a collection with your default item
$classes = array('person');

foreach ($terms as $term) {

    // add items
    $classes[] = $term->slug;

}

// output all the classes together with a space to separate them.
echo '<div class="' . implode(' ', $classes) . '">';

echo '<div>More markup for each person listing</div>';

---

EXCLUDING

To ignore adding any item:

if( $term->slug !== 'accounting' ) { $classes[] = $term->slug; }

To remove all bad apples:

$pros = array('A', 'B', 'C');
$cons = array('C');
$best = array_diff($pros, $cons);
print_r ($best); // A, B

---

In context:

$terms = get_the_terms( $post->ID, 'teams' );

// create a collection with your default item
$classes = array( 'person' );

if ( $terms && ! is_wp_error( $terms ) ) {
    foreach ( $terms as $term ) {
        $classes[] = $term->slug; // add items
    }
}

// remove any specific classes here
$classes = array_diff( $classes, array( 'creative-services' ) );

// output all the classes together with a space to separate them.
echo '<div class="' . implode( ' ', $classes ) . '">';

echo '<div>More markup for each person listing</div>';