WP hooks navigation: Home/browse • Actions index • Filters index
To save our bandwidth, we show only a snippet of code around each occurence of the hook. View complete file in SVN (without highlighting).
The best way to understand what a hook does is to look at where it occurs in the source code.
do_action( "hook_name" )
apply_filters( "hook_name", "what_to_filter" )
.Remember, this hook may occur in more than one file. Moreover, the hook's context may change from version to version.
Line | Code |
---|---|
196 | * |
197 | * @param null|bool $check Whether to allow updating metadata for the given type. |
198 | * @param int $object_id ID of the object metadata is for. |
199 | * @param string $meta_key Metadata key. |
200 | * @param mixed $meta_value Metadata value. Must be serializable if non-scalar. |
201 | * @param mixed $prev_value Optional. Previous value to check before updating. |
202 | * If specified, only update existing metadata entries with |
203 | * this value. Otherwise, update all entries. |
204 | */ |
205 | $check = apply_filters( "update_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $prev_value ); |
206 | if ( null !== $check ) { |
207 | return (bool) $check; |
208 | } |
209 |
|
210 | // Compare existing value to new value if no prev value given and the key exists only once. |
211 | if ( empty( $prev_value ) ) { |
212 | $old_value = get_metadata_raw( $meta_type, $object_id, $meta_key ); |
213 | if ( is_countable( $old_value ) && count( $old_value ) === 1 ) { |
214 | if ( $old_value[0] === $meta_value ) { |