如何用DWRUtil.getValues("Emp_Form");取得html:select标签的值

如何用DWRUtil.getValues("Emp_Form");取得html:select标签的值
我的标签如下

<html:select property="positionId" style="width:100">
     <c:forEach var="position" items="${positions}">
         <html:option value="${position.id }">${position.positionName }</html:option>
     </c:forEach>
</html:select>
DWRUtil.getValues使用这个取值时是根据控件ID去取的,可怎么给html:select加ID呢,
<html:select property="positionId" style="width:100" id="aa">会出错啊

<script. language="javascript" type="text/javascript">
   function getLanMuList(){

      alert("方法已经调用");
      var Lanmu = document.getElementById("lanmu");
      var Lanmu1 = document.getElementById("news.column_name");
      var index = Lanmu.selectedIndex;
      alert(index);
      var Lanmu_value = Lanmu.options[index].value;
      alert(Lanmu_value);
      if(Lanmu_value!="" || Lanmu_value!=null){
           alert("查询子栏目");
           NewsManager.getget();
        NewsManager.getLanMu(Lanmu_value,lanmuReturn);
        NewsManager.getget();
        alert("查询子栏目完毕");
      }else{
        DWRUtil.removeAllOptions(Lanmu1);  
                 DWRUtil.addOptions(Lanmu1,{'':'请选择'});  
      }

  
       var Lanmu = document.getElementById("lanmu");
    var Lanmu1 = document.getElementById("news.column_name");
    var index = Lanmu.selectedIndex;
    var Lanmu_value = Lanmu.options[index].value;
    if(Lanmu_value==""){
     DWRUtil.removeAllOptions(Lanmu1);  
     DWRUtil.addOptions(Lanmu1,{'':'请选择'});
    }else if(Lanmu_value!="" || Lanmu_value!=null){
        NewsManager.getLanMu(Lanmu_value,lanmuReturn);
    }

   }
   function lanmuReturn(data){
     var Lanmu1 = document.getElementById("news.column_name");
     DWRUtil.removeAllOptions(Lanmu1);  
             DWRUtil.addOptions(Lanmu1,{'':'请选择'});  
              DWRUtil.addOptions(Lanmu1,data);  
   }
  </script>

页面部分

<div class="add02" style="width: 100px；float :     left;">
     <select id="lanmu" nChange="getLanMuList()">
      <option selected value="">
       请选择
      </option>
      <c:forEach var="entry" items="${columnList}">
          <c:if test="${entry.next_column==0}">
        <option value="${entry.column_id}">
         ${entry.column_name}
        </option>
       </c:if>
      </c:forEach>
     </select>
    </div>
    <div class="add02" style="padding: 0 0 0 32px; width: 100px">
     子栏目：
    </div>
    <div class="add02" style="width: 100px；float :     left;">
     <select id="news.column_name" name ="news.column_name">
      <option selected value="">
       请选择
      </option>
     </select>
    </div>

??
虽然走题了,但还是和谢谢你的回复,可能我没表达清楚吧!我主要是想知道如何给html:select加ID这个属性

正确答案:
<html:select property="positionId" styleId="positionId">