public function GetCurrentUserId()
{
$result = null;
$this->dataset->AddFieldFilter($this->userNameFieldName, new FieldFilter($this->GetCurrentUser(), '=', true));
$this->dataset->Open();
if ($this->dataset->Next()) {
$result = $this->dataset->GetFieldValueByName($this->userIdFieldName);
}
$this->dataset->Close();
$this->dataset->ClearFieldFilters();
return $result;
}