这是根据中的示例改编的get_post_custom_keys().

function get_public_custom_fields( $post_id = 0 ) {
    if ( ! empty( $post_id ) )
        $custom_fields = get_post_custom( $post_id );
    else
        $custom_fields = get_post_custom();

    $public_custom_fields = array();
    foreach ( $custom_fields as $key => $value ) {
        if ( \'_\' != $key{0} )
            $public_custom_fields[$key] = $value;
    }

    return $public_custom_fields;
}