JS.CategoryHelper 缓存级下拉框多级联动

<script type="text/javascript">
         /*分类级联下拉框动态显示 Goosoz@163.com 2013-07*/
         function CategoryHelper(rootId, alllist) {
             function proClass(json) {
                 this.Id = json[0];
                 this.ParentId = json[1];
                 this.Name = json[2];
             }
             var list = new Array();
             for (var i = 0; i < alllist.length; i++) {
                 var item = new proClass(alllist[i]);
                 list.push(item);
             }

             //获取当前proClass
             function getProClass(id) {
                 for (var i = 0; i < list.length; i++) {
                     var item = list[i];
                     if (item.Id == id) { return item; }
                 }
                 return null;
             };
             //获取父辈proClass
             function getParent(id) {
                 var curItem = getProClass(id);
                 if (curItem == null) { return null; }

                 for (var i = 0; i < list.length; i++) {
                     var item = list[i];
                     if (item.Id == curItem.ParentId) { return item; }
                 }
                 return null;
             };
             //获取下级proClass
             function getChildrens(id) {
                 var arr = new Array();
                 for (var i = 0; i < list.length; i++) {
                     var item = list[i];
                     if (item.ParentId == id) {
                         arr.push(item);
                     }
                 }
                 return arr;
             };
             function getSiblings(id) {
                 var curItem = getProClass(id);
                 return getChildrens(curItem == null ? rootId : curItem.ParentId);
             };
             function getSelect(pId, id, arr) {
                 var html = "<select class=\"sitem\" pid=\"" + pId + "\">";
                 html += "<option value=\"" + pId + "\" " + (rootId == id ? "selected=\"selected\"" : "") + ">--</option>";
                 for (var i = 0; i < arr.length; i++) {
                     var item = arr[i];
                     html += "<option value=\"" + item.Id + "\" " + (item.Id == id ? "selected=\"selected\"" : "") + ">" + item.Name + "</option>";
                 }
                 html += "</select>";
                 return html;
             };
             //当前选中的ID
             this.CurID = 0;
             //当前选中的名称
             this.CurName = null;
             //当前选中的名称数组
             this.CurNameArray = new Array();
             //获取所有Select的Html
             this.getHtml = function (id) {
                 this.CurID = id;
                 this.CurName = null;
                 this.CurNameArray = new Array();

                 if (id == rootId) {
                     var arr = getChildrens(rootId);
                     return getSelect(rootId, rootId, arr);
                 } else {
                     var _cur = getProClass(id);
                     var _childrens = getChildrens(id);
                     var html = "";
                     while (_cur != null) {
                         this.CurNameArray.push(_cur.Name);
                         var _siblings = getSiblings(_cur.Id);
                         html = getSelect(_cur.ParentId, _cur.Id, _siblings) + html;
                         _cur = getProClass(_cur.ParentId);
                     }
                     if (_childrens.length > 0) {
                         html += getSelect(id, rootId, _childrens);
                     }
                     return html;
                 }
             };
         }
     </script>

 <div id="areabox"></div>

var JS_AddressJSON=[["110000","0","北京市"],["130000","0","河南省"],["210000","0","上海市"],["130100","130000","周口市"]];

     var pHelper = new CategoryHelper("0",JS_AddressJSON);
     var pHelper_DefaultID = JS_AreaID;
     $("#areabox").html(pHelper.getHtml(pHelper_DefaultID));
     $(document).on("change","#areabox select", function () {
         $("#areabox").html(pHelper.getHtml($(this).val()));
     });

     $("#btn-nextstep").click(function () {
         var  area = pHelper.CurID;
    
     });