效果图：
aaarticlea/png;base64,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" 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主要文件有Index.cshtml ,ErJLDController.cs ，还有数据库文件 。
1、首先在数据库中创建省级、城市的表，我的表如下：我用了一张表放下了省级、城市的数据，用level划分省份和城市，parentId表示该城市所在省份的id
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" alt="" />
namespace Mvcproject.Controllers
{
//二级联动
public class ErJLDController : Controller
{ ZjbEntities db = new ZjbEntities();
//
// GET: /Test/ public ActionResult Index()
{
//pro_city province=new pro_city(); return View();
} public JsonResult getProvince() { List<pro_city> provinceList = (from p in db.pro_city where p.level == 1 select p).ToList(); JsonResult Jprovince = new JsonResult();
Jprovince.Data = provinceList;
Jprovince.JsonRequestBehavior = JsonRequestBehavior.AllowGet;
return Jprovince; } public JsonResult getCity(string pName)
{ //string pid = (from p in db.pro_city where p.areaValue == pName select p.id).ToString();
//int id = int.Parse(pid);
int id = int.Parse(pName); List<pro_city> cityList = (from p in db.pro_city where p.parentId == id select p).ToList(); JsonResult Jcity = new JsonResult();
Jcity.Data = cityList;
Jcity.JsonRequestBehavior = JsonRequestBehavior.AllowGet;
return Jcity; } }
}
ErJLDController.cs
<body>
<div>
<select id="provinceId" >
<option> 请选择省份</option>
</select>
<select id="cityId">
<option>请选择市区</option>
</select>
</div> <script type="text/javascript"> //用json从数据库里取一级列表的参数
$(function () { $.getJSON("ErJLD/getProvince/", function (obj) {
$.each(obj, function (i, p) {
$("#provinceId").append("<option value='"+p.id+"'>" + p.areaValue + "</option>");
}); $("#provinceId").change(function () {
//用attr（）方法获取当前选择的option的value值（即p.id ,数据库里的id值，
//虽然在TestController中的getCity方法中传入的是string类型的形参，但是后来需要变换成int类型, 所以value值应该为数字）
var pName = $("#provinceId").attr("value");
$.getJSON("ErJLD/getCity?pName=" + pName, getcity);
});
});
}); function getcity(obj) {
$("#cityId").empty();
$.each(obj, function (m, v) {
$("#cityId").append("<option >" + v.areaValue + "</option>");
}); }; </script>
</body>
Index.cshtml