Question

add_metadata( string $meta_type,  int $object_id,  string $meta_key,  mixed $meta_value,  bool $unique = false )

Add metadata for the specified object.

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description

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参数

$meta_type

(string) (Required) Type of object metadata is for (e.g., comment, post, or user)

$object_id

(int) (Required) ID of the object metadata is for

$meta_key

(string) (Required) Metadata key

$meta_value

(mixed) (Required) Metadata value. Must be serializable if non-scalar.

$unique

(bool) (Optional) Whether the specified metadata key should be unique for the object. If true, and the object already has a value for the specified metadata key, no change will be made.

Default value: false

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返回值

(int|false) The meta ID on success, false on failure.

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源代码

File: wp-includes/meta.php

function add_metadata($meta_type, $object_id, $meta_key, $meta_value, $unique = false) {
	global $wpdb;

	if ( ! $meta_type || ! $meta_key || ! is_numeric( $object_id ) ) {
		return false;
	}

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

	$table = _get_meta_table( $meta_type );
	if ( ! $table ) {
		return false;
	}

	$column = sanitize_key($meta_type . '_id');

	// expected_slashed ($meta_key)
	$meta_key = wp_unslash($meta_key);
	$meta_value = wp_unslash($meta_value);
	$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type );

	/**
	 * Filters whether to add metadata of a specific type.
	 *
	 * The dynamic portion of the hook, `$meta_type`, refers to the meta
	 * object type (comment, post, or user). Returning a non-null value
	 * will effectively short-circuit the function.
	 *
	 * @since 3.1.0
	 *
	 * @param null|bool $check      Whether to allow adding metadata for the given type.
	 * @param int       $object_id  Object ID.
	 * @param string    $meta_key   Meta key.
	 * @param mixed     $meta_value Meta value. Must be serializable if non-scalar.
	 * @param bool      $unique     Whether the specified meta key should be unique
	 *                              for the object. Optional. Default false.
	 */
	$check = apply_filters( "add_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $unique );
	if ( null !== $check )
		return $check;

	if ( $unique && $wpdb->get_var( $wpdb->prepare(
		"SELECT COUNT(*) FROM $table WHERE meta_key = %s AND $column = %d",
		$meta_key, $object_id ) ) )
		return false;

	$_meta_value = $meta_value;
	$meta_value = maybe_serialize( $meta_value );

	/**
	 * Fires immediately before meta of a specific type is added.
	 *
	 * The dynamic portion of the hook, `$meta_type`, refers to the meta
	 * object type (comment, post, or user).
	 *
	 * @since 3.1.0
	 *
	 * @param int    $object_id  Object ID.
	 * @param string $meta_key   Meta key.
	 * @param mixed  $meta_value Meta value.
	 */
	do_action( "add_{$meta_type}_meta", $object_id, $meta_key, $_meta_value );

	$result = $wpdb->insert( $table, array(
		$column => $object_id,
		'meta_key' => $meta_key,
		'meta_value' => $meta_value
	) );

	if ( ! $result )
		return false;

	$mid = (int) $wpdb->insert_id;

	wp_cache_delete($object_id, $meta_type . '_meta');

	/**
	 * Fires immediately after meta of a specific type is added.
	 *
	 * The dynamic portion of the hook, `$meta_type`, refers to the meta
	 * object type (comment, post, or user).
	 *
	 * @since 2.9.0
	 *
	 * @param int    $mid        The meta ID after successful update.
	 * @param int    $object_id  Object ID.
	 * @param string $meta_key   Meta key.
	 * @param mixed  $meta_value Meta value.
	 */
	do_action( "added_{$meta_type}_meta", $mid, $object_id, $meta_key, $_meta_value );

	return $mid;
}

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更新日志

Version	description
2.9.0	Introduced.

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相关函数

Uses

• wp-includes/cache.php: wp_cache_delete()
• wp-includes/formatting.php: wp_unslash()
• wp-includes/formatting.php: sanitize_key()
• wp-includes/functions.php: absint()
• wp-includes/functions.php: maybe_serialize()
• wp-includes/plugin.php: apply_filters()
• wp-includes/plugin.php: do_action()
• wp-includes/wp-db.php: wpdb::get_var()
• wp-includes/wp-db.php: wpdb::insert()
• wp-includes/wp-db.php: wpdb::prepare()
• wp-includes/meta.php: _get_meta_table()
• wp-includes/meta.php: sanitize_meta()
• wp-includes/meta.php: add_{$meta_type}_metadata
• wp-includes/meta.php: add_{$meta_type}_meta
• wp-includes/meta.php: added_{$meta_type}_meta
Show 10 more uses Hide more uses

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Used By

• wp-includes/rest-api/fields/class-wp-rest-meta-fields.php: WP_REST_Meta_Fields::update_multi_meta_value()
• wp-includes/taxonomy.php: add_term_meta()
• wp-includes/user.php: add_user_meta()
• wp-includes/post.php: add_post_meta()
• wp-includes/comment.php: add_comment_meta()
• wp-includes/meta.php: update_metadata()
Show 1 more used by Hide more used by

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User Contributed Notes