MVC DropDownLis 二级联动实现

转自：https://bbs.csdn.net/topics/370096159
二级联动：
View： 
<script type="text/javascript">    
    $(function () {       
        $("#drpProvince").change(function () { 
            $("#drpCity").get(0).options.length = 0; //清空
            $.getJSON("/Persons/GetCities/" + $(this).val(), null , function (data) {
                $.each(data, function (i, item) {
                    $("<option></option>").val(item["ID"]).text(item["CityName"]).appendTo($("#drpCity"));
                });
            });
        });
    });
</script>
 
@Html.DropDownList("drpProvince",null,"请选择")
@Html.DropDownList("drpCity", null,"请选择")
 
Action：
 
          public ActionResult Create()
        { 
            List<Provinces> list = db.Provices.ToList();
            ViewData["drpProvince"] = new SelectList(list, "ID", "ProvinceName");
            ViewData["drpCity"] = new List<SelectListItem>();
            return View();
        }
 
        //返回城市列表
        public ActionResult GetCities(int? id)
        {
            List<Cities> list = db.Cities.Where(q => q.ProvincesID == id).ToList();
            if (Request.IsAjaxRequest())
            {
                return Json(list, JsonRequestBehavior.AllowGet);
            }
            else
            {
                return View("");
            }
        } 