后台获取数据做为前台的数据源：

public JSONArray getArray()throws Exception{JSONArray jo=new JSONArray();String id = "",superId = "",name = "";JSONObject children=new JSONObject();List<Area> list = (List<Area>) queryByList();for (Area area:list) {id = area.getArea_id()+"";superId = area.getParent_id()+"";name = area.getArea_name();children.put("id", id);children.put("pId", superId);children.put("name", name);jo.add(children);children.clear();}return jo;        }

jsp中的js脚本：

<script language="javascript" > function load(){var areaArray = ${areaArray};var area = new CLASS_LIANDONG(areaArray);            // 设置数据源area.firstSelectChange("0","prov");                    // 设置第一个选择框area.subSelectChange("prov","city");                // 设置子级选择框area.subSelectChange("city","area");                // 设置子级选择框 }function CLASS_LIANDONG(array){// 数组，联动的数据源this.array=array;this.indexName='';this.obj='';// 设置子SELECT// 参数：当前onchange的SELECT ID，要设置的SELECT IDthis.subSelectChange=function(selectName1,selectName2){var obj1=document.all[selectName1];var obj2=document.all[selectName2];var objName=this.toString();var me=this;obj1.onchange=function(){me.optionChange(this.options[this.selectedIndex].value,obj2.id);};}// 设置第一个SELECT// 参数：indexName指选中项,selectName指select的IDthis.firstSelectChange=function(indexName,selectName){this.obj=document.all[selectName];this.indexName=indexName;this.optionChange(this.indexName,this.obj.id);}// indexName指选中项,selectName指select的IDthis.optionChange=function (indexName,selectName){var obj1=document.all[selectName];var me=this;obj1.length=0;obj1.options[0]=new Option("请选择",'');for(var i=0;i<this.array.length;i++){    if(this.array[i].pId==indexName){obj1.options[obj1.length]=new Option(this.array[i].name,this.array[i].id);}}}}
</script><li><em>所属省市：</em><div><select name="prov" id="prov" style="width: 74px;height: 25px" ><option selected>省份</option></select><select name="city" id="city" style="width: 74px;height: 25px" ><option selected>城市</option></select></div></li>

修改页面赋初值:

$("#prov").val(1).change();//利用代码触发change事件
$("#city").val(2);