How to get first level subsections by section id?

Question

1C-Bitrix

And you need to get the value of the custom field of the sections UF_SORT_F of these internal sections of the first level
, it didn’t work out, it
gives an array without UF_SORT_F
///Array ( [NAME] => Buyers with this product [ID] => 838 [SORT] => 500 ) /// //////Array ( [NAME] => GOST [ID] => 842 [SORT] => 500 ) /////////Array ( [NAME] => Assigned [ID] => 843 [SORT] => 501 ) /////////Array ( [NAME] => By form [ID] => 845 [SORT] => 503 ) /////////Array ( [NAME] => Accessories [ID] => 844 [SORT] => 504 ) //////

if ( CModule::IncludeModule ( "iblock" ) ){
    $arOrder = array("sort" => "ASC");
    $arFilter = array("SECTION_ID" => 820);
    $arSelect = array("NAME", "ID","UF_SORT_F");

    $db_elemens = CIBlockSection::GetList ( $arOrder, $arFilter, false,  $arSelect );
    while ( $arElement = $db_elemens->Fetch () ) {
        echo "///";
        print_r($arElement);
        echo $uf_value["ID"];
        echo "///";
        echo $uf_value["NAME"];
        echo "///";
        echo $uf_value["UF_SORT_F"];
        echo $arElement["DESCRIPTION"];
    }

}
}

this is how it happened, but I don’t know how to get the UF_SORT_F field

if(CModule::IncludeModule("iblock"))
{
    // если $ID не задан или это не число, тогда
    // $ID будет =0, выбираем корневые разделы
    $ID = IntVal(820);
    // выберем папки из информационного блока $BID и раздела $ID
    $items = GetIBlockSectionList(28, $ID, Array("UF_SORT"=>"asc"), 10);
    while($arItem = $items->GetNext())
    {
print_r($arItem);
       echo $arItem["NAME"];
        echo $arItem["UF_SORT_F"];
    }
}
else
    ShowError("Модуль не установлен");

Answer 1

Pass in the IBLOCK_ID filter.