How to create property from property with multiple value and update after exchange?

Question

1C-Bitrix

The product has the property "details"

How can I take one subproperty from there and enter it as a separate property of the product, while updating it during the exchange and not touching it again?

Answer 1

VicTHOR , in general terms, I see this:
1) creating the OnAfterIBlockElementAdd handler in init.php (after creating the element)
and OnAfterIBlockElementUpdate (changing the element) during the exchange
2) Getting the Details data in the CIBlockElement::GetPropertyValues ​​handler (for a multiple property of the string type)
3 ) CIBlockElement::SetPropertyValues ​​(Set a new value for this property of this element)

Answer 2

There was such a task when exchanging with 1s. The weight was unloaded in the form of props. Here is the complete code for getting the given value and updating it in another sv.

$db_res = CIBlockElement::GetList(
        array(),
        array('IBLOCK_ID' => 1, 'IBLOCK_TYPE' => 'catalog', 'ACTIVE' => 'Y'),
        false,
        false
    );


while ($ar_res = $db_res->Fetch())
{
    if(isset($ar_res['IBLOCK_SECTION_ID'])){
      $ID = $ar_res['ID'];
      // все поля
      $ar_res2 = CCatalogProduct::GetByIDEx($ID);
      
       $property_enums = CIBlockPropertyEnum::GetList(Array("DEF" => "DESC", "SORT" => "ASC"), Array("IBLOCK_ID" => $ar_res["IBLOCK_ID"], "CODE" => "VES"));
       $arPropertyArchive = [];
        while($enum_fields = $property_enums->GetNext()) {
           /* Если значение равно "Да" */
           if ($enum_fields["VALUE"] == $ar_res2['PROPERTIES']['CML2_TRAITS']['VALUE']) {
              $arPropertyArchive = Array(
                 "VES" => $enum_fields["ID"],
              );
              break;
           }
        }
       if(empty($arPropertyArchive)){
       	$ibpenum = new CIBlockPropertyEnum;
    $PropID = $ibpenum->Add(Array('PROPERTY_ID'=> 396, 'VALUE'=>$ar_res2['PROPERTIES']['CML2_TRAITS']['VALUE']));
       		$arPropertyArchive = array(
       			'VES' => $PropID
       		);
       }
      CIBlockElement::SetPropertyValuesEx($ar_res['ID'], $ar_res['IBLOCK_ID'], $arPropertyArchive, ['DoNotValidateLists']);
      echo "========================================================================";
  }
}