<tr>                               
       <td class="left">省:</td>  
       <td><input name="contact.province" id="province" style="width: 174px;" ></td>     
       <td class="left">市:</td>          
       <td><input  name="contact.city" id="city" style="width: 174px;"></td>                       
       <td class="left">县区:</td>  
       <td><input name="contact.county" id="county" style="width: 174px;" ></td>
    </tr>

$(function(){
 
 // 下拉框选择控件，下拉框的内容是动态查询数据库信息
 $('#province').combobox({ 
    url:'apply/provinceCombobox_combobox.action',
    editable:false, //不可编辑状态
    cache: false,
   // panelHeight: 'auto',//自动高度适合
    valueField:'code',  
    textField:'note',
    
 onHidePanel: function(){

   $("#city").combobox("setValue",'');
   $("#county").combobox("setValue",'');
   $("#cregicounty").val('');
  var province = $('#province').combobox('getValue'); 
  if(province!=''){
  $.ajax({
  type: "POST",
  url: "apply/cityCombobox_combobox.action"+province,
  cache: false,
  dataType : "json",
  success: function(data){
  $("#city").combobox("loadData",data);
                 }
                }); 
              }
           } 
         }); 
 
 $('#city').combobox({ 

   editable:false, //不可编辑状态
   cache: false,
   //panelHeight: 'auto',//自动高度适合
   valueField:'code',  
   textField:'note',
   onHidePanel: function(){
   $("#cregicounty").val('');
   $("#county").combobox("setValue",'');
  var city = $('#city').combobox('getValue'); 
  if(city!=''){
  $.ajax({
  type: "POST",
  url: "apply/countyCombobox_combobox.action"+city,
  cache: false,
  dataType : "json",
  success: function(data){
  $("#county").combobox("loadData",data);
                 }
                }); 
              }
           }
  }); 
 $('#county').combobox({ 
   editable:false, //不可编辑状态
   cache: false,
  // panelHeight: 'auto',//自动高度适合
   valueField:'code',  
   textField:'note',
   onHidePanel: function(){
     var str=$('#county').combobox('getText');
   $("#cregicounty").val(str); 
           }
 }); 
 
  $('#country').combobox({//国家代码初始化 
 valueField:'english',  
   textField:'note',
   url:'json/country.json',
   cache: false,
  //panelHeight: 'auto',//自动高度适合
   onChange: function(newValue,oldValue){ 

   countrySearch(newValue);
   countrys(newValue);
   }
 });
}); 

//查询全国行政区代码省
 public String provinceCombobox() throws Exception{
 
 List list=comboboxService.findProvince();
 this.jsonUtil(list);
 return null;
 }
 
 //查询全国行政区代码市
 public String cityCombobox() throws Exception{
  
 List list=comboboxService.findCity(province);
 this.jsonUtil(list);
   return null;
 }
 
 //查询全国行政区代码县区
 public String countyCombobox() throws Exception{
 
 List list=comboboxService.findCounty(city);
 this.jsonUtil(list);
   return null;
 }
 
 
 //调用json工具方法，传入参数alist
 public void jsonUtil(Object accountlist) throws Exception{
  HttpServletResponse response = ServletActionContext.getResponse(); 
  log.info("JSON格式：" + accountlist.toString());
  
  String returnJson = JsonConvert.returnJson(accountlist);
  response.setCharacterEncoding("utf-8");
  response.getWriter().println(returnJson);
 }

import java.io.StringWriter;

import org.codehaus.jackson.map.ObjectMapper;

public class JsonConvert {
 static String jsonStr;
 public static String returnJson(Object object) throws Exception{
 ObjectMapper objectMapper = new ObjectMapper();
 StringWriter stringWriter = new StringWriter();
 objectMapper.writeValue(stringWriter, object);
 
 jsonStr = stringWriter.toString();
 return jsonStr;
 }
}

//查询省
public List findProvince() throws Exception;
//查询市
public List findCity(String code) throws Exception;
//查询县区
public List findCounty(String code) throws Exception;

 //下拉框--查询省
 public List findProvince() {
 log.info("===下拉框--查询省");

 Criteria criteria=this.sessionFactory.getCurrentSession().createCriteria(CareacodeTblQg.class);
 criteria.add(Restrictions.like("code", "%0000"));
 criteria.addOrder(Order.asc("code"));
 
 return criteria.list();
 }
 
 //下拉框--查询市
 public List findCity(String code2) {
 log.info("===下拉框--查询市");
 String id=code2.substring(0,2);

 Criteria criteria=this.sessionFactory.getCurrentSession().createCriteria(CareacodeTblQg.class);
 criteria.add(Restrictions.like("code", id+"%00"));
 criteria.add(Restrictions.ne("code",code2 ));
 criteria.addOrder(Order.asc("code"));
 
 return criteria.list();
 }
 
 //下拉框--查询县区
 public List findCounty(String code3) {
 log.info("===下拉框--查询县区");

 String id=code3.substring(0,4);
 Criteria criteria=this.sessionFactory.getCurrentSession().createCriteria(CareacodeTblQg.class); 
 
 criteria.add(Restrictions.like("code", id+"%"));
 criteria.add(Restrictions.not(Restrictions.like("code", "%01")));
 criteria.add(Restrictions.ne("code",code3 ));
 criteria.addOrder(Order.asc("code"));
 
 return criteria.list();
 }