public static function textToDatabase($conn, $dir, SpatialFileInterface $spatialfile)
 {
     $textData = SpatialFileMethods::getTextData($dir, $spatialfile);
     $field_names = SpatialFileMethods::checkTextDataFields($textData);
     $result = SpatialFileMethods::createSpatialfileTable($dir, $spatialfile, $field_names, $conn, 'spatial_' . str_replace('-', '_', $spatialfile->getId()));
     if ($result) {
         $spatialfile->setFieldList(serialize($field_names));
         $rowCount = SpatialFileMethods::insertTextDataToTable($textData, $field_names, $conn, 'spatial_' . str_replace('-', '_', $spatialfile->getId()));
         if ($rowCount === 0) {
             return null;
         }
     }
     return $field_names;
 }