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filter is not described

pre_add_site_option_(option) filter-hook . WP 3.0.0

Filters the value of a specific network option before it is added.

The dynamic portion of the hook name, $option, refers to the option name.

Usage

add_filter( 'pre_add_site_option_(option)', 'filter_function_name_9317', 10, 3 );
function filter_function_name_9317( $value, $option, $network_id ){
	// filter...

	return $value;
}
$value(mixed)
Value of network option.
$option(string)
Option name.
$network_id(int)
ID of the network.

Changelog

Since 3.0.0 Introduced.
Since 2.9.0 As 'pre_add_site_option_' . $key
Since 4.4.0 The $option parameter was added.
Since 4.7.0 The $network_id parameter was added.

Where the hook is called

add_network_option()
pre_add_site_option_(option)
wp-includes/option.php 1366
$value = apply_filters( "pre_add_site_option_{$option}", $value, $option, $network_id );

Where the hook is used (in WP core)

Usage not found!