</span>
                    </div>
                </td>
            </tr>
            <tr>
                <td>
                    <label><span><strong><?php 
_e('Type', 'wpdatatables');
?>
</strong></span>:</label>
                </td>    
                <td>
                    <div class="columnType">
                        <select class="columnType">
                            <?php 
foreach (WDTTools::getPossibleColumnTypes() as $columnTypeKey => $columnTypeName) {
    ?>
                            <option value="<?php 
    echo $columnTypeKey;
    ?>
"><?php 
    echo $columnTypeName;
    ?>
</option>
                            <?php 
}
?>
                        </select>
                    </div>
                </td>
            </tr>
 /**
  * Generates a table based on the provided file and shows a preview
  */
 public function previewFileTable($table_data)
 {
     if (!empty($table_data['file'])) {
         $xls_url = urldecode($table_data['file']);
         if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
             $xls_url = str_replace(site_url(), str_replace('\\', '/', ABSPATH), $xls_url);
         } else {
             $xls_url = str_replace(site_url(), ABSPATH, $xls_url);
         }
     } else {
         return _('Empty file', 'wpdatatables');
     }
     require_once WDT_ROOT_PATH . '/lib/phpExcel/PHPExcel.php';
     $objPHPExcel = new PHPExcel();
     if (strpos(strtolower($xls_url), '.xlsx')) {
         $objReader = new PHPExcel_Reader_Excel2007();
         $objReader->setReadDataOnly(true);
     } elseif (strpos(strtolower($xls_url), '.xls')) {
         $objReader = new PHPExcel_Reader_Excel5();
         $objReader->setReadDataOnly(true);
     } elseif (strpos(strtolower($xls_url), '.ods')) {
         $objReader = new PHPExcel_Reader_OOCalc();
         $objReader->setReadDataOnly(true);
     } elseif (strpos(strtolower($xls_url), '.csv')) {
         $objReader = new PHPExcel_Reader_CSV();
     } else {
         return _('File format not supported!', 'wpdatatables');
     }
     $objPHPExcel = $objReader->load($xls_url);
     $objWorksheet = $objPHPExcel->getActiveSheet();
     $highestRow = $objWorksheet->getHighestRow();
     $highestRow = $highestRow > 5 ? 5 : $highestRow;
     $highestColumn = $objWorksheet->getHighestColumn();
     $headingsArray = $objWorksheet->rangeToArray('A1:' . $highestColumn . '1', null, true, true, true);
     $headingsArray = $headingsArray[1];
     $r = -1;
     $namedDataArray = array();
     for ($row = 2; $row <= $highestRow; ++$row) {
         $dataRow = $objWorksheet->rangeToArray('A' . $row . ':' . $highestColumn . $row, null, true, true, true);
         if (isset($dataRow[$row]['A']) && $dataRow[$row]['A'] > '') {
             ++$r;
             foreach ($headingsArray as $dataColumnIndex => $dataColumnHeading) {
                 $namedDataArray[$r][$dataColumnHeading] = $dataRow[$row][$dataColumnIndex];
                 if (WDT_DETECT_DATES_IN_EXCEL) {
                     $cellID = $dataColumnIndex . $row;
                     if (PHPExcel_Shared_Date::isDateTime($objPHPExcel->getActiveSheet()->getCell($cellID))) {
                         $namedDataArray[$r][$dataColumnHeading] = PHPExcel_Shared_Date::ExcelToPHP($dataRow[$row][$dataColumnIndex]);
                     }
                 }
             }
         }
     }
     $columnTypeArray = WDTTools::detectColumnDataTypes($namedDataArray, $headingsArray);
     $possibleColumnTypes = WDTTools::getPossibleColumnTypes();
     $ret_val = '';
     if (!empty($namedDataArray)) {
         ob_start();
         include WDT_TEMPLATE_PATH . 'constructor_file_preview.inc.php';
         $ret_val = ob_get_contents();
         ob_end_clean();
     }
     return $ret_val;
 }