WordPress at a glance
filter is not described

woocommerce_process_checkout_(type)_field filter-hook . WC 1.0

phpcs:enable WordPress.Security.NonceVerification.Missing

Usage

add_filter( 'woocommerce_process_checkout_(type)_field', 'filter_function_name_1515' );
function filter_function_name_1515( $apply_filters ){
	// filter...

	return $apply_filters;
}
$apply_filters
-

Where the hook is called

WC_Checkout::get_posted_data()
woocommerce_process_checkout_(type)_field
woocommerce/includes/class-wc-checkout.php 711
$data[ $key ] = apply_filters( 'woocommerce_process_checkout_' . $type . '_field', apply_filters( 'woocommerce_process_checkout_field_' . $key, $value ) );

Where in WP core the hook is used WooCommerce

Usage not found.