 <td>
                <select class="ui dropdown auto-width" name="format">
                    <option value="xlsx">Excel</option>
                    <option value="csv">CSV</option>
                    <option value="txt">TXT</option>
                    <option value="json">JSON</option>
                </select>
            </td>
        </tr>
    </table>
    <submit-btn>导出</submit-btn>
</form>