
使用不同的方法获取WordPress文章和页面ID
get_metadata_default ( $meta_type, $object_id, $meta_key, $single = false )
get_metadata_default函数用于检索给定元数据键的默认值: 这个函数可以用来为没有被设置的自定义元数据提供一个默认值。
检索指定元键和对象的默认元数据值。
默认情况下,如果`$single`为真,则返回一个空字符串,如果为假,则返回一个空数组。
function get_metadata_default( $meta_type, $object_id, $meta_key, $single = false ) { if ( $single ) { $value = ''; } else { $value = array(); } /** * Filters the default metadata value for a specified meta key and object. * * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type * (post, comment, term, user, or any other type with an associated meta table). * * Possible filter names include: * * - `default_post_metadata` * - `default_comment_metadata` * - `default_term_metadata` * - `default_user_metadata` * * @since 5.5.0 * * @param mixed $value The value to return, either a single metadata value or an array * of values depending on the value of `$single`. * @param int $object_id ID of the object metadata is for. * @param string $meta_key Metadata key. * @param bool $single Whether to return only the first value of the specified `$meta_key`. * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user', * or any other object type with an associated meta table. */ $value = apply_filters( "default_{$meta_type}_metadata", $value, $object_id, $meta_key, $single, $meta_type ); if ( ! $single && ! wp_is_numeric_array( $value ) ) { $value = array( $value ); } return $value; }