bitrix.prev.next.links.php

<?

$arFilter = array("IBLOCK_ID" => $arResult["IBLOCK_ID"], "ACTIVE" => "Y");
if (!empty($arResult["IBLOCK_SECTION_ID"])) {
	$arFilter["IBLOCK_SECTION_ID"] = $arResult["IBLOCK_SECTION_ID"];
}
$resNav = CIBlockElement::GetList(
	array(
		$arParams['SORT_BY1'] => $arParams['SORT_ORDER1'],
		$arParams['SORT_BY2'] => $arParams['SORT_ORDER2'],
	),
	$arFilter,
	false,
	array("nPageSize" => 1, "nElementID" => $arResult["ID"]),
	array("ID", "DETAIL_PAGE_URL", "NAME")
);
$arNav = array();
while ($item = $resNav->GetNext()) {
	$arNav[] = $item;
}


if (count($arNav) > 2) {
	$arResult["NEXT"] = $arNav[0];
	$arResult["PREV"] = $arNav[2];
} else {
	if ($arNav[0]["ID"] == $arResult["ID"]) {
		$arResult["NEXT"] = false;
		$arResult["PREV"] = $arNav[1];
	} else {
		$arResult["NEXT"] = $arNav[0];
		$arResult["PREV"] = false;
	}
}