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sanitize_(object_type)_meta_(meta_key)_for_(object_subtype) filter-hook . WP 4.9.8

Filters the sanitization of a specific meta key of a specific meta type and subtype.

The dynamic portions of the hook name, $object_type, $meta_key, and $object_subtype, refer to the metadata object type (comment, post, term or user), the meta key value, and the object subtype respectively.

Usage

add_filter( 'sanitize_(object_type)_meta_(meta_key)_for_(object_subtype)', 'filter_function_name_3749', 10, 4 );
function filter_function_name_3749( $meta_value, $meta_key, $object_type, $object_subtype ){
	// filter...

	return $meta_value;
}
$meta_value(mixed)
Meta value to sanitize.
$meta_key(string)
Meta key.
$object_type(string)
Object type.
$object_subtype(string)
Object subtype.

Where the hook is called

sanitize_meta()
wp-includes/meta.php 1040
return apply_filters( "sanitize_{$object_type}_meta_{$meta_key}_for_{$object_subtype}", $meta_value, $meta_key, $object_type, $object_subtype );

Where the hook is used (in WP core)

wp-includes/meta.php 1159
add_filter( "sanitize_{$object_type}_meta_{$meta_key}_for_{$object_subtype}", $args['sanitize_callback'], 10, 4 );
wp-includes/meta.php 1226
remove_filter( "sanitize_{$object_type}_meta_{$meta_key}_for_{$object_subtype}", $args['sanitize_callback'] );