<form action="<?= base_url() . $action ?>" method="post">
    <fieldset class="form"> 
        <label>
            <b><?= lang('search_with') ?></b>
        </label>
        <input name="userdata" class="textBox sml rnd5"/>
        <input type="submit" value="<?= lang('search_b') ?>" name="search_by_userdata" class="button sub inlineBlock rnd3 lightTextShadow" />            
    </fieldset>
</form>

