thinkphp HTML页面循环输出 和if判断

<volist name="result" id="vo">
          <div>
          <span><font color="blue"><a>{Weiyuntian:$vo.title}</a></font></span>
          <span style="float:right;">
            <font color="blue">日期：{Weiyuntian:$vo.add_time}</font>
          </span>
          </div>
 </volist>

<option value="2" οnclick="sort()"  <if condition="$sort eq 2">selected="selected"</if> >同步时间（升序）</option>