AddEventHandler("catalog", "OnBeforeProductUpdate", "myOnBeforeProductUpdate");
function myOnBeforeProductUpdate($id, &$arFields)
{
$arItem = CIBlockElement::GetList(false, array('IBLOCK_ID' => 59, 'ID' => $id), false, false, array('ID', 'PROPERTY_STATUS_POD_ZAKAZ'))->fetch();
if ($arItem['PROPERTY_STATUS_POD_ZAKAZ_VALUE'] == 'Да') {
$arFields['QUANTITY_TRACE'] = 'N';
$arFields['CAN_BUY_ZERO'] = 'Y';
} else {
$arFields['QUANTITY_TRACE'] = 'D';
$arFields['CAN_BUY_ZERO'] = 'D';
}
}
function BXIBlockAfterSave($arFields) {
IBlockElementAfterSaveHandler($arFields);
ваш код...
}