.net MVC 下拉多级联动及编辑

多级联动实现，附源码。当前，部分代码是参与博客园其它网友。

新增，前台代码：

<script src="~/Scripts/jquery-1.10.2.js"></script>
<script type="text/javascript">
    $(function () {
        GetProvince(); //加载省份
        $("#Province").change(function () {
            GetCity();
        });
    });
    function GetProvince() {
        //        $("#Province").empty();
        $.getJSON(
            "/Home/GetProvincelist",
            function (data) {

                $.each(data, function (i, item) {
                    $("<option></option>").val(item["PID"]).text(item["ProvinceName"]).appendTo($("#Province"));
                })
            });
        //            GetCity();
    }
    function GetCity() {
        $("#City").empty();
        $.getJSON(
        "/Home/GetCitylist",
        { pid: $("#Province").val() },
        function (data) {
            $.each(data, function (i, item) {
                $("<option></option>").val(item["Value"]).text(item["Text"]).appendTo($("#City"));

            })
        });
    }
</script>
<div style="margin:50px 0">
    <span>省份：</span>
    <select id="Province">
        <option>请选择</option>
    </select>

    <span>市：</span>
    <select id="City">
        <option>请选择</option>
    </select>
</div>

后台代码：

        /// <summary>
        /// 模拟省份数据
        /// </summary>
        /// <returns></returns>
        public List<Province> Provincelist()
        {
            List<Province> list = new List<Province>();
            list.Add(new Province() { PID = 1, ProvinceName = "广东" });
            list.Add(new Province() { PID = 2, ProvinceName = "北京" });
            list.Add(new Province() { PID = 3, ProvinceName = "上海" });
            list.Add(new Province() { PID = 4, ProvinceName = "河北" });
            list.Add(new Province() { PID = 5, ProvinceName = "贵州" });
            list.Add(new Province() { PID = 6, ProvinceName = "云南" });

            return list;
        }

        /// <summary>
        /// 模拟城市数据
        /// </summary>
        /// <returns></returns>
        public List<City> Citylist()
        {
            List<City> cityList = new List<City>();
            cityList.Add(new City() { CID = 1, PID = 1, CityName = "广州" });
            cityList.Add(new City() { CID = 2, PID = 1, CityName = "深圳" });
            cityList.Add(new City() { CID = 3, PID = 1, CityName = "惠州" });
            cityList.Add(new City() { CID = 4, PID = 1, CityName = "湛江" });
            cityList.Add(new City() { CID = 5, PID = 2, CityName = "北京" });
            cityList.Add(new City() { CID = 6, PID = 3, CityName = "上海" });
            cityList.Add(new City() { CID = 7, PID = 4, CityName = "唐山市" });
            cityList.Add(new City() { CID = 8, PID = 4, CityName = "保定市" });
            cityList.Add(new City() { CID = 9, PID = 4, CityName = "张家口市" });
            return cityList;
        }

        /// <summary>
        /// 获取省份
        /// </summary>
        public JsonResult GetProvincelist()
        {
            var list = Provincelist();
            return Json(list, JsonRequestBehavior.AllowGet);
        }

        /// <summary>
        /// 获取城市
        /// </summary>
        /// <param name="pid"></param>
        /// <returns></returns>
        public JsonResult GetCitylist(int pid)
        {
            var citys = Citylist().Where(m => m.PID == pid).ToList();

            List<SelectListItem> item = new List<SelectListItem>();

            foreach (var City in citys)
            {
                item.Add(new SelectListItem { Text = City.CityName, Value = City.CID.ToString() });
            }
            return Json(item, JsonRequestBehavior.AllowGet);
        }

　　

编辑逻辑：

模型ProvinceViewModel：

    public class ProvinceViewModel
    {
        /// <summary>
        /// 省份ID
        /// </summary>
        public int PID { get; set; }

        /// <summary>
        /// 城市ID
        /// </summary>
        public int CID { get; set; }
    }

前台：

<script src="~/Scripts/jquery-1.10.2.js"></script>
<script type="text/javascript">
    $(function () {
        //GetProvince(); //加载省份
        GetCity();
        //省份变动，加载城市
        $("#Province").change(function () {
            GetCity();
        });
    });
    function GetProvince() {
        //        $("#Province").empty();
        $.getJSON(
            "/Home/GetProvincelist",
            function (data) {

                $.each(data, function (i, item) {
                    $("<option></option>").val(item["PID"]).text(item["ProvinceName"]).appendTo($("#Province"));
                })
            });
        //            GetCity();
    }
    function GetCity() {
        $("#City").empty();
        $.getJSON(
        "/Home/GetCitylist",
        { pid: $("#Province").val() },
        function (data) {
            $.each(data, function (i, item) {
                $("<option></option>").val(item["Value"]).text(item["Text"]).appendTo($("#City"));

            })
        });
    }
</script>
<div style="margin:50px 0">
    <span>省份：</span>
    @Html.DropDownListFor(model => model.PID, ViewBag.ProvinceList as IEnumerable<SelectListItem>, "＝请选择＝", new { @class = "form-control", id = "Province" })

    <span>市：</span>
    @Html.DropDownListFor(model => model.CID,ViewBag.CityList  as IEnumerable<SelectListItem>, "＝请选择＝", new { @class = "form-control", id = "City" })
</div>

　后台：

        public ActionResult Edit()
        {
            ViewBag.ProvinceList = Provincelist().Select(m => new SelectListItem()
            {
                Text = m.ProvinceName,
                Value = m.PID.ToString(),
                Selected = (m.PID == 4) //测试，默认让它绑定第四个
            }).ToList();
            ViewBag.CityList = Citylist().Select(m => new SelectListItem()
            {
                Text = m.CityName,
                Value = m.CID.ToString(),
                Selected = (m.CID == 8) //测试，默认让它绑定第四个
            }).ToList();
            return View();
        }

　　

实际上，增加和编辑是完成可以合成同一个页面的，这里就不演示了。

源代码下载：点击下载