JQuery Ajax三级联动地区下拉框

JSP部分代码
 
  
 
 <script src="/js/jquery-1.2.6.min.js" type="text/javascript"></script>
 <script>
  //为了避免jquery中的'$'与其它的'$'冲突,在此将jquery中的'$'重命名为'jQuery'
  var jQuery=$;
 </script>
 
 
  
 
 <script>
 
 
   //初始化数据
   jQuery(document).ready(function(){
  
    getProvince();
 
  });
  
 
  
   
   //取所有省份
   function getProvince(){
 
    //&callback=?"注意这个是为了解决跨域访问的问题   
    var url ="http://www.yimei.com/shopcar/getAreaJSON?areaId=0&callback=?";
    
    jQuery.getJSON(url,null,function call(result){   
          setProvince(result); 
      });
    
    //显示或隐藏激活卡
    jQuery("#actionCardChk").click(function(){
     if(jQuery("#actionCardChk").attr("checked")==true){
      jQuery("#actionCardDiv").show();
     }else{
      jQuery("#actionCardDiv").hide();
     }
    });
    
    //显示或隐藏新增常用地址
    jQuery("#addressChk").click(function(){
     if(jQuery("#addressChk").attr("checked")==true){
      jQuery("#addressDiv").show();
     }else{
      jQuery("#addressDiv").hide();
     }
    });
    
    
   }
   
   
   
   
   //设置省份
   function setProvince(result){
   
   var province = document.getElementById("toProvince");
   
   jQuery.each(result.data, function(i, area){
          var value = area.id;
     var text = area.name;
     var option = new Option(text,value);
     province.options.add(option);
           
     });  
   
   }
   
   
   //按上级ID取子地区
   function getArea(name){
    
    if( name=='city' ){
     clearSel(document.getElementById("toCity")); //清空城市
     var province = document.getElementById("toProvince");
     if(province.options[province.selectedIndex].value == "") return;
     var areaId = province.options[province.selectedIndex].value;
     
     var url ="http://www.yimei.com/shopcar/getAreaJSON?areaId="+areaId+"&callback=?";
     jQuery.getJSON(url,null,function call(result){   
           setCity(result); 
       });
      
    }else if( name=='county'){
     clearSel(document.getElementById("toCounty")); //清空城区
     var city = document.getElementById("toCity");
     if(city.options[city.selectedIndex].value == "") return;
     var areaId = city.options[city.selectedIndex].value;
     
     var url ="http://www.yimei.com/shopcar/getAreaJSON?areaId="+areaId+"&callback=?";
     jQuery.getJSON(url,null,function call(result){   
           setCounty(result); 
       });
       
    }
   }
   
   //当改变省份时设置城市
   function setCity(result){
   
   var city = document.getElementById("toCity");
   
   jQuery.each(result.data, function(i, area){
          var value = area.id;
     var text = area.name;
     var option = new Option(text,value);
     city.options.add(option);
     });  
     
   }
   
   
   //当改变省份时设置城市
   function setCounty(result){
  
   var county = document.getElementById("toCounty");
   
   jQuery.each(result.data, function(i, area){
          var value = area.id;
     var text = area.name;
     var option = new Option(text,value);
     county.options.add(option);
     });  
    
   }
   
   // 清空下拉列表
   function clearSel(oSelect){
      
   while(oSelect.childNodes.length>0){
    oSelect.removeChild(oSelect.childNodes[0]);
   }
          
   }
 
  
 
 </script>
 
  
 
   <tr>
   <td height="28" colspan="3"> 
    <select name="toProvince" id="toProvince" onChange="getArea('city')" class="STYLE5" onFocus="doOnFocus(this);">
     <option value="" selected>请选择省份...</option>
    </select>         
   </td> 
          </tr>
 
          <tr>
   <td height="28" colspan="3">               
    <select name="toCity" id="toCity" class="board" onChange="getArea('county')" onFocus="doOnFocus(this);">
     <option value="">请选择城市...</option>
    </select>        
   </td>
                 
          </tr>
          
          <tr>
   <td class="STYLE3">
    <select name="toCounty" id="toCounty" class="board"  onfocus="doOnFocus(this);">
     <option value="">请选择城区...</option>
    </select>        
   </td>
  </tr>
 
  
 
  
 
 JAVA部分代码 Servlet
 
  
 
  response.setContentType("text/xml;charset=utf-8");
   response.setHeader("Pragma","No-cache");
   response.setDateHeader("Expires",0);
   response.setHeader("Cache-Control","no-cache");    
   PrintWriter out=response.getWriter();
 
   String areaId = request.getParameter("areaId");
   
   if(areaId==null || areaId.trim().length()<=0){
    //sb.append("<data><error>系统错误地区id为空</error></data>");
    //out.print(sb.toString());
    return;
   }  
   
 
   //注意这个是为了解决跨域访问的问题
   String callback = request.getParameter("callback");   
   
   try {
 
    List areaList = AreaService.getInstance().getAreasByParentId(Integer.parseInt(areaId));
 
    // 取集合
    JSONArray jsonArray = JSONArray.fromObject(areaList);
 
    JSONObject jsobjcet = new JSONObject();
 
    jsobjcet.put("data", jsonArray);
    
    response.getWriter().write(callback+"("+jsobjcet.toString()+");");
 
    log.info(callback+"("+jsobjcet.toString()+");");
    
    
   } catch (IOException e) {
    e.printStackTrace();
   }
      
 
  
 
 DAO部分代码
 
 public List getAreasByParentId(int parentId) {
   Connection conn=null;
   Statement stm=null;
   ResultSet rs=null;
   List<AreaInfo> list = new ArrayList<AreaInfo>();
   try{
    conn = ConnectionPool.getConnection();
    if( conn == null ) throw new Exception("DataBase connection error");
    stm = conn.createStatement();
    String sql ="select * from n_area where parent_id =" + parentId;
    rs = stm.executeQuery(sql);
    AreaInfo areaInfo = null;
    while( rs.next() ) {
     areaInfo= new AreaInfo();
     areaInfo.setId(rs.getInt("id"));
     areaInfo.setName(rs.getString("name"));
     areaInfo.setParentId(rs.getInt("parent_id"));
     list.add(areaInfo);
    }
   }catch(Exception e){
    log.error("getAreasByParentId() error:"+e.getMessage());
   }finally{
    ConnectionPool.release(conn,stm,rs); //释放资源
   }
   return list;
  }
 
  
 
  
 
 数据表结构
 
 CREATE TABLE `n_area` (
   `id` int(11) NOT NULL auto_increment,
   `name` varchar(20) default NULL,
   `parent_id` int(11) NOT NULL default '0',
   PRIMARY KEY  (`id`)
 ) ENGINE=MyISAM AUTO_INCREMENT=224 DEFAULT CHARSET=gbk;
 
 记录
 
  
 
 INSERT INTO `n_area` VALUES ('1', '广东省', '0');
 INSERT INTO `n_area` VALUES ('2', '北京', '0');
 INSERT INTO `n_area` VALUES ('3', '深圳市', '1');
 INSERT INTO `n_area` VALUES ('4', '广州市', '1');
 INSERT INTO `n_area` VALUES ('5', '北京五环以内', '2');
 INSERT INTO `n_area` VALUES ('6', '天津', '0');
 INSERT INTO `n_area` VALUES ('7', '天津市', '6');
 INSERT INTO `n_area` VALUES ('14', '珠海市', '1');
 INSERT INTO `n_area` VALUES ('15', '汕头市', '1');
 INSERT INTO `n_area` VALUES ('16', '佛山市', '1');
 INSERT INTO `n_area` VALUES ('17', '东莞市', '1');
 INSERT INTO `n_area` VALUES ('22', '肇庆市', '1');
 INSERT INTO `n_area` VALUES ('23', '惠州市', '1');
 INSERT INTO `n_area` VALUES ('24', '清远市', '1');
 INSERT INTO `n_area` VALUES ('25', '韶关市', '1');
 INSERT INTO `n_area` VALUES ('26', '湛江市', '1');
 INSERT INTO `n_area` VALUES ('27', '潮州市', '1');
 INSERT INTO `n_area` VALUES ('28', '梅州市', '1');
 INSERT INTO `n_area` VALUES ('29', '茂名市', '1');
 INSERT INTO `n_area` VALUES ('30', '浙江省', '0');
 INSERT INTO `n_area` VALUES ('31', '江苏省', '0');
 INSERT INTO `n_area` VALUES ('32', '福建省', '0');
 INSERT INTO `n_area` VALUES ('33', '广西省', '0');
 INSERT INTO `n_area` VALUES ('34', '江西省', '0');
 INSERT INTO `n_area` VALUES ('35', '山东省', '0');
 INSERT INTO `n_area` VALUES ('36', '湖南省', '0');
 INSERT INTO `n_area` VALUES ('37', '安徽省', '0');
 INSERT INTO `n_area` VALUES ('38', '贵州省', '0');
 INSERT INTO `n_area` VALUES ('39', '黑龙江省', '0');
 INSERT INTO `n_area` VALUES ('40', '辽宁省', '0');
 INSERT INTO `n_area` VALUES ('41', '四川省', '0');
 INSERT INTO `n_area` VALUES ('42', '湖北省', '0');
 INSERT INTO `n_area` VALUES ('43', '陕西省', '0');
 INSERT INTO `n_area` VALUES ('44', '河南省', '0');
 INSERT INTO `n_area` VALUES ('45', '山西省', '0');
 INSERT INTO `n_area` VALUES ('46', '海南省', '0');
 INSERT INTO `n_area` VALUES ('47', '杭州市', '30');
 INSERT INTO `n_area` VALUES ('48', '温州市', '30');
 INSERT INTO `n_area` VALUES ('49', '宁波市', '30');
 INSERT INTO `n_area` VALUES ('50', '台州市', '30');
 INSERT INTO `n_area` VALUES ('51', '南京市', '31');
 INSERT INTO `n_area` VALUES ('52', '无锡市', '31');
 INSERT INTO `n_area` VALUES ('53', '苏州市', '31');
 INSERT INTO `n_area` VALUES ('54', '常州市', '31');
 INSERT INTO `n_area` VALUES ('55', '徐州市', '31');
 INSERT INTO `n_area` VALUES ('56', '福州市', '32');
 INSERT INTO `n_area` VALUES ('57', '厦门市', '32');
 INSERT INTO `n_area` VALUES ('58', '泉州市', '32');
 INSERT INTO `n_area` VALUES ('59', '漳州市', '32');
 INSERT INTO `n_area` VALUES ('60', '南宁市', '33');
 INSERT INTO `n_area` VALUES ('61', '桂林市', '33');
 INSERT INTO `n_area` VALUES ('62', '柳州市', '33');
 INSERT INTO `n_area` VALUES ('63', '百色市', '33');
 INSERT INTO `n_area` VALUES ('64', '南昌市', '34');
 INSERT INTO `n_area` VALUES ('65', '赣州市', '34');
 INSERT INTO `n_area` VALUES ('66', '济南市', '35');
 INSERT INTO `n_area` VALUES ('67', '青岛市', '35');
 INSERT INTO `n_area` VALUES ('68', '长沙市', '36');
 INSERT INTO `n_area` VALUES ('69', '合肥市', '37');
 INSERT INTO `n_area` VALUES ('70', '贵阳市', '38');
 INSERT INTO `n_area` VALUES ('71', '哈尔滨市', '39');
 INSERT INTO `n_area` VALUES ('72', '大连市', '40');
 INSERT INTO `n_area` VALUES ('73', '成都市', '41');
 INSERT INTO `n_area` VALUES ('74', '武汉市', '42');
 INSERT INTO `n_area` VALUES ('75', '西安市', '43');
 INSERT INTO `n_area` VALUES ('76', '郑州市', '44');
 INSERT INTO `n_area` VALUES ('77', '太原市', '45');
 INSERT INTO `n_area` VALUES ('78', '海口市', '46');
 INSERT INTO `n_area` VALUES ('79', '中山市', '1');
 INSERT INTO `n_area` VALUES ('80', '顺德市', '1');
 INSERT INTO `n_area` VALUES ('81', '江门市', '1');
 INSERT INTO `n_area` VALUES ('82', '云浮市', '1');
 INSERT INTO `n_area` VALUES ('83', '阳江市', '1');
 INSERT INTO `n_area` VALUES ('84', '揭阳市', '1');
 INSERT INTO `n_area` VALUES ('85', '河源市', '1');
 INSERT INTO `n_area` VALUES ('86', '重庆', '0');
 INSERT INTO `n_area` VALUES ('87', '重庆市区', '86');
 INSERT INTO `n_area` VALUES ('88', '上海', '0');
 INSERT INTO `n_area` VALUES ('89', '上海市', '88');
 INSERT INTO `n_area` VALUES ('91', '北京五环以外', '2');
 INSERT INTO `n_area` VALUES ('93', '重庆郊区', '86');
 INSERT INTO `n_area` VALUES ('94', '河北省', '0');
 INSERT INTO `n_area` VALUES ('95', '石家庄市', '94');
 INSERT INTO `n_area` VALUES ('96', '保定市', '94');
 INSERT INTO `n_area` VALUES ('97', '邯郸市', '94');
 INSERT INTO `n_area` VALUES ('98', '张家口市', '94');
 INSERT INTO `n_area` VALUES ('99', '秦皇岛市', '94');
 INSERT INTO `n_area` VALUES ('100', '邢台市', '94');
 INSERT INTO `n_area` VALUES ('101', '唐山市', '94');
 INSERT INTO `n_area` VALUES ('102', '承德市', '94');
 INSERT INTO `n_area` VALUES ('103', '镇江市', '31');
 INSERT INTO `n_area` VALUES ('104', '绍兴市', '30');
 INSERT INTO `n_area` VALUES ('105', '嘉兴市', '30');
 INSERT INTO `n_area` VALUES ('106', '南通市', '31');
 INSERT INTO `n_area` VALUES ('107', '扬州市', '31');
 INSERT INTO `n_area` VALUES ('108', '连云港市', '31');
 INSERT INTO `n_area` VALUES ('109', '北海市', '33');
 INSERT INTO `n_area` VALUES ('110', '九江市', '34');
 INSERT INTO `n_area` VALUES ('111', '景德镇市', '34');
 INSERT INTO `n_area` VALUES ('112', '淄博市', '35');
 INSERT INTO `n_area` VALUES ('113', '烟台市', '35');
 INSERT INTO `n_area` VALUES ('114', '潍坊市', '35');
 INSERT INTO `n_area` VALUES ('115', '威海市', '35');
 INSERT INTO `n_area` VALUES ('116', '岳阳市', '36');
 INSERT INTO `n_area` VALUES ('117', '湘潭市', '36');
 INSERT INTO `n_area` VALUES ('118', '株洲市', '36');
 INSERT INTO `n_area` VALUES ('119', '衡阳市', '36');
 INSERT INTO `n_area` VALUES ('120', '常德市', '36');
 INSERT INTO `n_area` VALUES ('121', '滁州市', '37');
 INSERT INTO `n_area` VALUES ('123', '安庆市', '37');
 INSERT INTO `n_area` VALUES ('124', '遵义市', '38');
 INSERT INTO `n_area` VALUES ('125', '安顺市', '38');
 INSERT INTO `n_area` VALUES ('126', '六盘水市', '38');
 INSERT INTO `n_area` VALUES ('127', '沈阳市', '40');
 INSERT INTO `n_area` VALUES ('128', '鞍山市', '40');
 INSERT INTO `n_area` VALUES ('129', '攀枝花市', '41');
 INSERT INTO `n_area` VALUES ('130', '南充市', '41');
 INSERT INTO `n_area` VALUES ('131', '襄樊市', '42');
 INSERT INTO `n_area` VALUES ('132', '黄石市', '42');
 INSERT INTO `n_area` VALUES ('133', '汉中市', '43');
 INSERT INTO `n_area` VALUES ('134', '洛阳市', '44');
 INSERT INTO `n_area` VALUES ('135', '开封市', '44');
 INSERT INTO `n_area` VALUES ('136', '云南省', '0');
 INSERT INTO `n_area` VALUES ('137', '昆明市', '136');
 INSERT INTO `n_area` VALUES ('138', '丽江市', '136');
 INSERT INTO `n_area` VALUES ('139', '蚌埠市', '37');
 INSERT INTO `n_area` VALUES ('140', '南山区', '3');
 INSERT INTO `n_area` VALUES ('141', '其它区', '3');
 INSERT INTO `n_area` VALUES ('143', '市北区', '67');
 INSERT INTO `n_area` VALUES ('213', '西藏', '0');
 INSERT INTO `n_area` VALUES ('178', '甘肃省', '0');
 INSERT INTO `n_area` VALUES ('179', '兰州市', '178');
 INSERT INTO `n_area` VALUES ('180', '内蒙古', '0');
 INSERT INTO `n_area` VALUES ('181', '呼和浩特', '180');
 INSERT INTO `n_area` VALUES ('182', '吉林省', '0');
 INSERT INTO `n_area` VALUES ('183', '新疆省', '0');
 INSERT INTO `n_area` VALUES ('184', '新疆', '183');
 INSERT INTO `n_area` VALUES ('185', '吉林市', '182');
 INSERT INTO `n_area` VALUES ('215', '其他地区', '213');
 INSERT INTO `n_area` VALUES ('187', '其他地区', '1');
 INSERT INTO `n_area` VALUES ('188', '其他地区', '30');
 INSERT INTO `n_area` VALUES ('189', '其他地区', '31');
 INSERT INTO `n_area` VALUES ('190', '其他地区', '32');
 INSERT INTO `n_area` VALUES ('191', '其他地区', '33');
 INSERT INTO `n_area` VALUES ('192', '其他地区', '34');
 INSERT INTO `n_area` VALUES ('193', '其他地区', '35');
 INSERT INTO `n_area` VALUES ('194', '其他地区', '36');
 INSERT INTO `n_area` VALUES ('195', '其他地区', '37');
 INSERT INTO `n_area` VALUES ('196', '其他地区', '38');
 INSERT INTO `n_area` VALUES ('197', '其他地区', '39');
 INSERT INTO `n_area` VALUES ('198', '其他地区', '40');
 INSERT INTO `n_area` VALUES ('199', '其他地区', '41');
 INSERT INTO `n_area` VALUES ('200', '其他地区', '42');
 INSERT INTO `n_area` VALUES ('201', '其他地区', '43');
 INSERT INTO `n_area` VALUES ('202', '其他地区', '44');
 INSERT INTO `n_area` VALUES ('203', '其他地区', '94');
 INSERT INTO `n_area` VALUES ('204', '其他地区', '136');
 INSERT INTO `n_area` VALUES ('205', '其他地区', '178');
 INSERT INTO `n_area` VALUES ('206', '其他地区', '180');
 INSERT INTO `n_area` VALUES ('207', '其他地区', '182');
 INSERT INTO `n_area` VALUES ('214', '拉萨', '213');
 INSERT INTO `n_area` VALUES ('210', '其他地区', '45');
 INSERT INTO `n_area` VALUES ('211', '其他地区', '46');
 INSERT INTO `n_area` VALUES ('212', '其他地区', '86');
 INSERT INTO `n_area` VALUES ('220', '新三区', '184');
 INSERT INTO `n_area` VALUES ('219', '新二区', '184');
 INSERT INTO `n_area` VALUES ('221', '天河区', '4');
 INSERT INTO `n_area` VALUES ('222', '越秀区', '4');
 INSERT INTO `n_area` VALUES ('223', '海珠区', '4');
 
  
 
  
 
 附件中有相应的jar包
 
 json-lib-2.1-jdk15.jar 是主要的