ajax异步读取后台传递回的下拉选项的值方法

<tr>  <td class="tdcell_word2">请选择展会：</td>  <td class="tdcell_word3" colspan="3"><select name="select" id="jieci" onchange="getChange()"><option value="">选择展会</option></select><script Language="JavaScript">loadjieci('- 选择展会 -');</script><span style="color:red;"> *</span><span style="font-size:12px;color:red;" id="mesjieci"></span>   </td></tr>

<script Language="JavaScript">function loadjieci(str) {/** 异步加载届次 */$.getJSON("/DictsAction.do?actionType=jieci",function (responseData, status) {if (status != "") {$("#jieci").empty();$("<option/>").html("- 选择展会 -").val("- 选择展会 -").appendTo("#jieci");$(responseData).each(function (n) {$("<option/>").html(this.name).val(this.code).appendTo("#jieci");});//默认显示请选择$("#jieci").val(str);} else {alert("届次加载失败！");}});}</script>

<!-- ajax异步加载字典 --><action path="/DictsAction" type="oa.sys016.oagzxxgl.action.DictsAction" scope="request" />

package oa.sys016.oagzxxgl.action;import java.io.PrintWriter;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import net.sf.json.JSONArray;import org.apache.struts.action.Action;import org.apache.struts.action.ActionForm;import org.apache.struts.action.ActionForward;import org.apache.struts.action.ActionMapping;import cn.com.chx.bo.AppBo;/** * 通过ajax加载届次选择下拉列表的选择项 * @author liu * */public class DictsAction extends Action{private AppBo appBo = null;@Overridepublic ActionForward execute(ActionMapping mapping, ActionForm form,HttpServletRequest request, HttpServletResponse response)throws Exception {// 设置编码response.setContentType("application/json;charset=UTF-8");response.setCharacterEncoding("UTF-8");PrintWriter out = response.getWriter();appBo = new AppBo();try {// 获取ActionTypeString actionType = request.getParameter("actionType");if (actionType != null && actionType.equals("jieci")) { // 查询届次String jieciJson = getJieciJson();out.print(jieciJson);}} catch (Exception e) {e.printStackTrace();} finally {out.close();}return null;}private String getJieciJson() {// 查询届次List jieciList;try {jieciList = appBo.query("SELECT ID AS CODE,ZH_NAME AS NAME FROM ZH_GZ_INFOX");List<Map<String, String>> lists = new ArrayList<Map<String, String>>();if (jieciList.size() > 0) {for (int i = 0; i < jieciList.size(); i++) {Map<String, String> maps = new HashMap<String, String>();maps.put("code",(String) ((HashMap) jieciList.get(i)).get("CODE"));maps.put("name",(String) ((HashMap) jieciList.get(i)).get("NAME"));lists.add(maps);}}// [{"id":"1","name":"CIMT2015"},{"id":"2","name":"CCMT2016"}] JSONArray json = JSONArray.fromObject(lists);return json.toString();} catch (Exception e) {e.printStackTrace();}return null;}}