js 菜单下拉跳转

<select id="unit_id" οnchange="location=this.options[this.selectedIndex].value">
    <option>--试题类型--</option>
    <?php foreach($s_lists as $k=>$v):?>
    <option <?php echo ($t_id == $k)?"selected=selected":"";?> value="<?php echo U('bank/index/compact_disc_id/'.$cid.'/exam_id/'.$eid.'/bank_type_id/'.$k)?> "><?php echo $v?>     </option> 
    <?php endforeach; ?>
    
    </select>

 

其中：οnchange="location=this.options[this.selectedIndex].value"非常重要