省市联动

（1）加载省

<select style="width: 100px;" name="province" id="province" onchange="changeProvince(this.value);"  class="form-control">
    <option >==省==</option>
    <c:forEach items="${provinces }" var="entry">
        <option value="${entry.provinceid }">${entry.province }</option>
    </c:forEach>
</select>

（2）替换市
通过οnchange=”changeProvince(this.value);”进行替换：得到该省份的ID，查询该省份所有城市
js代码：

    function changeProvince(code) {
            var url = "/csdn/manage/city.do";
            var params = {"code":code};
            $.post(url,params,function(data){
                var citys = data.citys;
                var html = "";
                for(var i = 0;i < citys.length;i++){
                    html += '<option value="'+ citys[i].city +'" >' + citys[i].city + '</option>';
                }
                $("#city").html(html);
            },"json");
        }

controller代码：

    @RequestMapping(value = "/manage/city.do")
    public void city(String code,HttpServletResponse response){

        CityExample example = new CityExample();
        example.createCriteria().andFatherEqualTo(code);
        List<City> citys = cityMapper.selectByExample(example);

        JSONObject jo = new JSONObject();
        jo.put("citys", citys);
        ResponseUtils.renderJson(response, jo.toString());
    }