get_the_terms( int|WP_Post $post, string $taxonomy )

检索附加到文章的分类术语。
Retrieve the terms of the taxonomy that are attached to the post.

目录锚点：#参数#返回#源码#笔记

参数（Parameters）

返回（Return）

（WP}u Term[]|false|WP}u Error）WP}u Term对象的数组，成功时为false，如果没有术语或post不存在，则为false，失败时为WP}u Error。

源码（Source）

/**
 * Retrieve the terms of the taxonomy that are attached to the post.
 *
 * @since 2.5.0
 *
 * @param int|object $post Post ID or object.
 * @param string $taxonomy Taxonomy name.
 * @return array|false|WP_Error Array of term objects on success, false if there are no terms
 *                              or the post does not exist, WP_Error on failure.
 */
function get_the_terms( $post, $taxonomy ) {
	if ( ! $post = get_post( $post ) )
		return false;

	$terms = get_object_term_cache( $post->ID, $taxonomy );
	if ( false === $terms ) {
		$terms = wp_get_object_terms( $post->ID, $taxonomy );
		wp_cache_add($post->ID, $terms, $taxonomy . '_relationships');
	}

	/**
	 * Filter the list of terms attached to the given post.
	 *
	 * @since 3.1.0
	 *
	 * @param array|WP_Error $terms    List of attached terms, or WP_Error on failure.
	 * @param int            $post_id  Post ID.
	 * @param string         $taxonomy Name of the taxonomy.
	 */
	$terms = apply_filters( 'get_the_terms', $terms, $post->ID, $taxonomy );

	if ( empty( $terms ) )
		return false;

	return $terms;
}

笔记（Notes）

WP_Term对象属性：（因为我一直在寻找它们）
获取所有自定义分类的术语
获得逗号分隔的术语列表的优化方法。

WP_Term Object
(
    [term_id] => 
    [name] => 
    [slug] => 
    [term_group] => 
    [term_taxonomy_id] => 
    [taxonomy] => 
    [description] => 
    [parent] => 
    [count] => 
    [filter] => 
)

$term_obj_list = get_the_terms( $post->ID, 'taxonomy' );
$terms_string = join(', ', wp_list_pluck($term_obj_list, 'name'));

function wpdocs_custom_taxonomies_terms_links() {
    // Get post by post ID.
    if ( ! $post = get_post() ) {
        return '';
    }
 
    // Get post type by post.
    $post_type = $post->post_type;
 
    // Get post type taxonomies.
    $taxonomies = get_object_taxonomies( $post_type, 'objects' );
 
    $out = array();
 
    foreach ( $taxonomies as $taxonomy_slug => $taxonomy ){
 
        // Get the terms related to post.
        $terms = get_the_terms( $post->ID, $taxonomy_slug );
 
        if ( ! empty( $terms ) ) {
            $out[] = "<h2>" . $taxonomy->label . "</h2>\n<ul>";
            foreach ( $terms as $term ) {
                $out[] = sprintf( '<li><a href="%1$s">%2$s</a></li>',
                    esc_url( get_term_link( $term->slug, $taxonomy_slug ) ),
                    esc_html( $term->name )
                );
            }
            $out[] = "\n</ul>\n";
        }
    }
    return implode( '', $out );
}

foreach ( get_the_terms( get_the_ID(), 'taxonomy_name' ) as $tax ) {
    echo '<li>' . __( $tax->name ) . '</li>';
}