get_metadata_raw

函数
get_metadata_raw ( $meta_type, $object_id, $meta_key = '', $single = false )
参数
  • (string) $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user', or any other object type with an associated meta table.
    Required:
  • (int) $object_id ID of the object metadata is for.
    Required:
  • (string) $meta_key Optional. Metadata key. If not specified, retrieve all metadata for the specified object. Default empty.
    Required:
    Default: (empty)
  • (bool) $single Optional. If true, return only the first value of the specified `$meta_key`. This parameter has no effect if `$meta_key` is not specified. Default false.
    Required:
    Default: false
返回值
  • (mixed) An array of values if `$single` is false. The value of the meta field if `$single` is true. False for an invalid `$object_id` (non-numeric, zero, or negative value), or if `$meta_type` is not specified. Null if the value does not exist.
定义位置
相关方法
get_metadataget_metadata_defaultget_metadata_by_middelete_metadataget_commentdata
引入
5.5.0
弃用
-

get_metadata_raw函数用于检索一个给定对象(例如一个文章、评论或用户)和元数据键的原始元数据: 这个函数可以用来检索未经处理或格式化的元数据。

检索指定对象的原始元数据值。

function get_metadata_raw( $meta_type, $object_id, $meta_key = '', $single = false ) {
	if ( ! $meta_type || ! is_numeric( $object_id ) ) {
		return false;
	}

	$object_id = absint( $object_id );
	if ( ! $object_id ) {
		return false;
	}

	/**
	 * Short-circuits the return value of a meta field.
	 *
	 * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
	 * (post, comment, term, user, or any other type with an associated meta table).
	 * Returning a non-null value will effectively short-circuit the function.
	 *
	 * Possible filter names include:
	 *
	 *  - `get_post_metadata`
	 *  - `get_comment_metadata`
	 *  - `get_term_metadata`
	 *  - `get_user_metadata`
	 *
	 * @since 3.1.0
	 * @since 5.5.0 Added the `$meta_type` parameter.
	 *
	 * @param mixed  $value     The value to return, either a single metadata value or an array
	 *                          of values depending on the value of `$single`. Default null.
	 * @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.
	 */
	$check = apply_filters( "get_{$meta_type}_metadata", null, $object_id, $meta_key, $single, $meta_type );
	if ( null !== $check ) {
		if ( $single && is_array( $check ) ) {
			return $check[0];
		} else {
			return $check;
		}
	}

	$meta_cache = wp_cache_get( $object_id, $meta_type . '_meta' );

	if ( ! $meta_cache ) {
		$meta_cache = update_meta_cache( $meta_type, array( $object_id ) );
		if ( isset( $meta_cache[ $object_id ] ) ) {
			$meta_cache = $meta_cache[ $object_id ];
		} else {
			$meta_cache = null;
		}
	}

	if ( ! $meta_key ) {
		return $meta_cache;
	}

	if ( isset( $meta_cache[ $meta_key ] ) ) {
		if ( $single ) {
			return maybe_unserialize( $meta_cache[ $meta_key ][0] );
		} else {
			return array_map( 'maybe_unserialize', $meta_cache[ $meta_key ] );
		}
	}

	return null;
}

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