@param int $id

@return bool|null
490439
public function removeFromSelection($id) {
        if($product = Product::get()->byID($id)) {
            $all = $this->getSelectionIDs();

            if(isset($all[$id])) {
                unset($all[$id]);
            }

            $this->setSelectionIDs($all);

            return true;
        }

        return null;
    }
330693
public function findChild($id)
    {
        foreach ($this->getChildren() as $child) {
            $result = $this->findChildInNode($child, $id);

            if ($result) {
                return $result;
            }
        }

        return null;
    }
590420
protected function iblockGetById($id)
    {
        $res = CIBlock::getList([], [
            'ID' => (int) $id,
            'CHECK_PERMISSIONS' => 'N',
        ]);

        return $res->fetch() ?: null;
    }
1178782
protected function doFetch($id)
    {
        $found = false;
        $val = $this->delegate->get($id, null, $found);
        if ($found) {
            return $val;
        } else {
            return false;
        }
    }
401521
public function getDataById($id)
    {
        $id = (int)$id;
        return array_key_exists($id, $this->_data) ? $this->_data[$id] : null;
    }
254780
public function findOneById($id)
    {
        try {
            return $this->_documentHandler->getById($this->_collectionName, $id);
        } catch (ServerException $e) {
            if ($e->getServerMessage() === 'document not found') {
                return null;
            }
            throw $e;
        }
    }
839746
public function find($id)
    {
        return isset($this->rows[$id]) ? $this->instanceRow($this->rows[$id], $this->realRows ? : $this) : null;
    }
1138932
public function delete( $id = null ) {

		if ( null === $id ) {
			$id = $this->id();
		}

		$id = (int) $this->do_hook( 'delete', $id );

		if ( empty( $id ) ) {
			return false;
		}

		$params = array(
			'pod' => $this->pod,
			'id'  => $id,
		);

		return $this->api->delete_pod_item( $params );
	}
1302501
public function get($id)
	{
		$data = $this->_get($id);
		return is_array($data) ? $data['data'] : FALSE;
	}
1142911
public function get($id) {
		if (! $this->connectionCheckStatus) {
			$this->addServer();
		}
		
		$result = $this->getClient()->get($this->prepareId($id));
		
		return $result === false ? null : $result;
	}
773718
public function id($id = null)
    {
        if (is_null($id)) {
            return $this->id;
        }

        $this->id = $id;

        return $this;
    }
590268
public function get($id)
    {
        foreach ($this->items as $item) {
            if ($item->id === $id) {
                return $item;
            }
        }
        return null;
    }
121701
public function deleteRow (int $id) : bool
	{
		$this->id = $id;
		return $this->delete() ? TRUE : FALSE;
	}
1124850
public function getById($id)
    {
        $list = $this->getByCriteria($id, $this->getUniqueId());
        return reset($list);
    }
310123
public function get($id = null){
        if(!is_null($id)){
            return $this->find($id);
        }
        return $this->model->get();
    }
1131656
public function getById(int $id)
    {
        $result = $this->builder->getById($id);

        if (isset($result[0])) {
            return self::instance($result[0]);
        }

        return null;
    }
1119835
public function find($id)
    {
        $this->newQuery();

        $this->queryBuilder->whereEqual($this->primaryFieldName, $id);

        $queryKey = $this->queryBuilder->firstQueryKey();

        if (!$this->isCompleteKey($queryKey)) {
            return null;
        }

        list($method, $parameters) = $this->getFindMethodAndParameters();

        array_unshift($parameters, $queryKey);
        $value = call_user_func_array([$this->redClient, $method], $parameters);

        return $value;
    }