Jquery+json绑定带层次下拉框（select控件）

一、实现的效果图

备注：

1、主要实现添加类别绑定到Ztree树之后，select下拉框在不刷新页面的情况下，通过Jquery重新绑定问题，增加用户体验度；

2、这个只是实现两层的绑定，通过sql语句排列成树状结构，然后绑定到select控件上；

select * from NewsCategory  order by case when ParentId=0 then Id*10000 else ParentId*10000+Id end

二、主要代码

html代码

                <select id="pid" name="pid" runat="server">
                    <option value="0" data="|0|">不选父级类</option>
                </select>

Jquery代码

 　　　　　　　　　　　　　　//加载选择栏
                        var html = ['<option value="0">不选父级模块</option>'];
                        var data = eval(json.msg);//转换为json对象
                        var levelStr;//记录层级值
                        for (var key in data) {
                            var str = data[key].itemvalue;
                            var _p = str.split("|")[2];
                            var _c = data[key].pId;
                            //判断是否是二级分类
                            if (_p == _c) {
                                //判断是否是一级分类
                                if (_p != "") {
                                    levelStr = "┗━┻━";
                                }
                                else {
                                    levelStr = "┗━";
                                }
                                html.push('<option value="' + data[key].id + '">' + levelStr + data[key].name + '</option>');
                            }
                            $("select[name='pid']").empty().append(html.join(''));

json格式字符串

"[
{"id":31,"name":"\u65b0\u95fb\u4e2d\u5fc3","pid":0,"itemvalue":"|0|"},
{"id":51,"name":"\u4f01\u4e1a\u5feb\u8baf","pid":31,"itemvalue":"|0|31|"},
{"id":52,"name":"\u4f01\u4e1a\u516c\u544a","pid":31,"itemvalue":"|0|31|"},
{"id":53,"name":"\u884c\u4e1a\u52a8\u6001","pid":31,"itemvalue":"|0|31|"},
{"id":54,"name":"\u5173\u4e8e\u76df\u53cb\u634c\u634c","pid":0,"itemvalue":"|0|"},
{"id":55,"name":"\u4f01\u4e1a\u6982\u51b5","pid":54,"itemvalue":"|0|54|"},
{"id":56,"name":"\u4f01\u4e1a\u6587\u5316","pid":54,"itemvalue":"|0|54|"},
{"id":57,"name":"\u4f01\u4e1a\u53d1\u5c55","pid":54,"itemvalue":"|0|54|"},
{"id":58,"name":"\u8054\u7cfb\u6211\u4eec","pid":54,"itemvalue":"|0|54|"},

{"id":65,"name":"\u4ea7\u54c1\u670d\u52a1","pid":0,"itemvalue":"|0|"},
{"id":70,"name":"\u63a8\u8350\u670d\u52a1","pid":65,"itemvalue":"|0|65|"},
{"id":71,"name":"\u8ba1\u8d39\u65b9\u5f0f","pid":65,"itemvalue":"|0|65|"},
{"id":72,"name":"\u7528\u6237\u987b\u77e5","pid":65,"itemvalue":"|0|65|"},
{"id":73,"name":"\u7981\u5bc4\u8303\u56f4","pid":65,"itemvalue":"|0|65|"},
{"id":75,"name":"\u666e\u901a\u5feb\u9012","pid":70,"itemvalue":"|0|65|70|"},
{"id":76,"name":"\u7279\u79cd\u5feb\u4ef6","pid":70,"itemvalue":"|0|65|70|"}

......
]"

涉及的知识点：

1、记录层级值ItemValue的添加(即类别添加)

 　　　　if (model.ParentId == )
        {
            model.ItemValue = "|0|";
        }
        else
        {
            Express.Model.NewsCategory modelid = Express.BLL.NewsCategory.GetModel(model.ParentId);
            model.ItemValue = modelid.ItemValue + model.ParentId + "|";
        }

2、获取的json字符串(json.msg)

　　　　if (Express.BLL.NewsCategory.Insert(model) > )
       {
          return json.Serialize(new { code = , msg = GetJson() });
       }

　　//序列化，将对象转化为JSON字符串
    protected string GetJson()
    {
        //为启用 AFAX 的应用程序提供序列化和反序列化功能
        System.Web.Script.Serialization.JavaScriptSerializer json = new System.Web.Script.Serialization.JavaScriptSerializer();
        List<Express.Model.NewsCategory> list = new List<Express.Model.NewsCategory>();
        //获取管理员模块列表
        list = Express.BLL.NewsCategory.Get();
        //将对象转换为JSON字符串
        return json.Serialize(list);
    }