钩住save\\u post，检查类别是否已经存在（以避免在post编辑时重复创建）。如果类别不存在，请使用wp_insert_term 并使用wp_set_object_terms

add_action(\'save_post\', \'add_title_as_category\');

function add_title_as_category( $postid ) {
  if ( defined(\'DOING_AUTOSAVE\') && DOING_AUTOSAVE ) return;
  $post = get_post($postid);
  if ( $post->post_type == \'post\') { // change \'post\' to any cpt you want to target
    $term = get_term_by(\'slug\', $post->post_name, \'category\');
    if ( empty($term) ) {
      $add = wp_insert_term( $post->post_title, \'category\', array(\'slug\'=> $post->post_name) );
      if ( is_array($add) && isset($add[\'term_id\']) ) {
        wp_set_object_terms($postid, $add[\'term_id\'], \'category\', true );
      }
    }
  }
}