Ajax应用实例SpringMVC框架

ajax代码：
$.ajax( {
type : "post",
url : urlPath,
dataType : "json",
data : params,
async : false,
success : function(data) {
var selectpro = document.getElementById("cityid");

selectpro.options.length = 0; //动态删除select中的所有options
var secondpro = data.BuguMenu;

var secondpros = secondpro.split(";");
for ( var i = 0; i < secondpros.length; i++) {
var s = secondpros[i].split(",");
if (s != null) {
$("#cityid").append(
"<option value='" + s[0] + "'>" + s[1]+ "</option>"
);
}
}
}
})





java代码
public ModelAndView selectCity(HttpServletRequest request,
HttpServletResponse response,Object obj) throws Exception {
String provinceid = request.getParameter("provinceid");
List<ComSelectBean>  cityList =null;
if(provinceid!=null &&provinceid.equals("46000000")){
          cityList =comSelectService.selectMap("getCountyList1",provinceid);

}else if(provinceid!=null &&provinceid.equals("54000000")){

          cityList =comSelectService.selectMap("getCountyList1",provinceid);

}else{
          cityList =comSelectService.selectMap("getCityList",provinceid);

}

Map<String, Object> map=new HashMap<String, Object> ();
    String a="";
    String c="";

    for(int i=0;i<cityList.size();i++){
String Buguid = cityList.get(i).getCityCode();
String Buguname=cityList.get(i).getCityName();
if(a.equals("")){
a=a+Buguid+","+Buguname;
}else{
a=a+";"+Buguid+","+Buguname;
}
}
    if(cityList.size()!=0){
    String Buguid = "all";
    String Buguname = "----全部----";
    a = a + ";"+Buguid+","+Buguname;
    }
    if(a.equals("")){
    c=",----请选择----";
    }else{
    c=",----请选择----;"+a;
    }
map.put("BuguMenu", c);
    JSONObject json = JSONObject.fromObject(map);
response.setContentType("text/html;charset=UTF-8");
    response.getWriter().write(json.toString());
 
return null;
}