【ASP.NET】 MVC下拉框联动
这个case主要是我在做项目的时候遇到一个需要根据input控件输入的内容，动态填充dropdown list中的内容， 实现二者联动的需求。在搜索了一些资源后，这篇博客解决了我的问题，所以记录并转载一下。
转载自： https://www.jb51.net/article/88986.htm
数据库schema：
USE master GO IF EXISTS (SELECT * FROM sysdatabases WHERE name='MyAddressDB' ) DROP DATABASE MyAddressDB GO CREATE DATABASE MyAddressDB GO USE MyAddressDB GO IF EXISTS (SELECT * FROM sysobjects WHERE name='Province') DROP TABLE Province GO --省份表 CREATE TABLE Province ( ProvinceID INT IDENTITY(1,1) PRIMARY KEY, ProvinceName NVARCHAR(50) NOT NULL ) IF EXISTS (SELECT * FROM sysobjects WHERE name='City') DROP TABLE City GO --省份表 CREATE TABLE City ( CityID INT IDENTITY(1,1) PRIMARY KEY, CityName NVARCHAR(50) NOT NULL, ProvinceID INT REFERENCES dbo.Province(ProvinceID) NOT NULL ) --插入测试语句：【在网上找了一个省市数据库，把里面的数据导入我当前数据库中】 --开始 INSERT INTO dbo.Province SELECT ProvinceName FROM Temp.dbo.S_Province INSERT INTO dbo.City ( CityName, ProvinceID ) SELECT CityName, ProvinceID FROM Temp.dbo.S_City --结束 --测试插入成功与否 --SELECT * FROM dbo.Province --SELECT * FROM dbo.City
Model代码：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace JsonDataInMVC.Models
{
public class Province
{
public int ProvinceID { get; set; }
public string ProvinceName { get; set; }
}
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace JsonDataInMVC.Models
{
public class City
{
public int CityID { get; set; }
public string CityName { get; set; }
public int ProvinceID { get; set; }
}
}
DB Operator：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Configuration;
using JsonDataInMVC.Models;
using System.Data;
using System.Data.SqlClient;
namespace JsonDataInMVC.DBOperator
{
public class AddressHelper
{
/// <summary>
/// 连接字符串
/// </summary>
public string ConnectionString
{
get
{
return ConfigurationManager.ConnectionStrings["DBConnectionString"].ConnectionString;
}
}
/// <summary>
/// 获取所有的省份
/// </summary>
/// <returns></returns>
public List<Province> GetAllProvince()
{
List<Province> lstProvince = new List<Province>();
string sql = @"SELECT * FROM dbo.Province";
//ADO.NET连接方式访问数据库
//1.创建连接对象[连接字符串]
SqlConnection conn = new SqlConnection(ConnectionString);
//2.创建命令对象
SqlCommand cmd = new SqlCommand();
cmd.CommandText = sql;
cmd.CommandType = CommandType.Text;
cmd.Connection = conn;
//3.打开连接
conn.Open();
//4.发送命令
SqlDataReader reader= cmd.ExecuteReader();
//5.处理数据
while (reader.Read())
{
lstProvince.Add(new Province()
{
ProvinceID =Convert.ToInt32( reader["ProvinceID"]),
ProvinceName = reader["ProvinceName"].ToString()
});
}
//6.关闭连接
conn.Close();
reader.Close();
return lstProvince;
}
/// <summary>
/// 通过ProvinceID获取市的数据
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
public List<City> GetCityListByProvinceID(int id)
{
DataSet ds = new DataSet();
string sql = @"SELECT CityID,CityName FROM dbo.City WHERE ProvinceID=@ProvinceID";
//ADO.NET非连接方式访问数据库
//1.创建连接对象
SqlConnection conn = new SqlConnection(ConnectionString);
//2.创建数据适配器对象
SqlDataAdapter sda = new SqlDataAdapter(sql,conn);//这里还真必须这样写。不能像下面的两条注释语句那样写。
//sda.SelectCommand.Connection = conn;
//sda.SelectCommand.CommandText = sql;
sda.SelectCommand.CommandType = CommandType.Text;
sda.SelectCommand.Parameters.AddWithValue("@ProvinceID", id);//参数设置别忘了
//3.打开连接【注意，非链接模式下，连接的打开关闭，无所谓，不过还是打开好点。规范化】
conn.Open();
//4.发送命令
sda.Fill(ds);
//5.处理数据
//6关闭连接【【注意，非链接模式下，连接的打开关闭，无所谓，不过还是打开好点。规范化】】
conn.Close();
return DataTableToList<City>.ConvertToModel(ds.Tables[0]).ToList<City>();
}
}
}
DB转list
using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Reflection;
using System.Web;
namespace JsonDataInMVC.DBOperator
{
public static class DataTableToList<T> where T : new()
{
public static IList<T> ConvertToModel(DataTable dt)
{
//定义集合
IList<T> ts = new List<T>();
T t = new T();
string tempName = "";
//获取此模型的公共属性
PropertyInfo[] propertys = t.GetType().GetProperties();
foreach (DataRow row in dt.Rows)
{
t = new T();
foreach (PropertyInfo pi in propertys)
{
tempName = pi.Name;
//检查DataTable是否包含此列
if (dt.Columns.Contains(tempName))
{
//判断此属性是否有set
if (!pi.CanWrite)
continue;
object value = row[tempName];
if (value != DBNull.Value)
pi.SetValue(t, value, null);
}
}
ts.Add(t);
}
return ts;
}
}
}
controller：
using JsonDataInMVC.DBOperator;
using JsonDataInMVC.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
namespace JsonDataInMVC.Controllers
{
public class ProvinceController : Controller
{
private AddressHelper db;
public ProvinceController()
{
db = new AddressHelper();
}
// GET: Province
public ActionResult Index()
{
List<Province> lstProvince= db.GetAllProvince();
ViewBag.ListProvince = lstProvince;
return View();
}
public JsonResult GetAllCityByProvinceID(int id)
{
List<City> lstCity= db.GetCityListByProvinceID(id);
return Json(lstCity, JsonRequestBehavior.AllowGet);
}
}
}
View：
@using JsonDataInMVC.Models
@{
ViewBag.Title = "Index";
List<Province> lstProvince = ViewBag.ListProvince as List<Province>;
}
<h2>ProvinceIndex</h2>
<label>省份:</label>
<select id="myProvince">
@foreach (var item in lstProvince)
{
<option value="@item.ProvinceID">@item.ProvinceName</option>
}
</select>
<br/>
<hr />
<label>城市:</label>
<select id="myCity">
</select>
<script src="~/Scripts/jquery-1.10.2.js"></script>
<script type="text/javascript">
$(document).ready(function () {
$("#myProvince").change(function () {
//获取省份的ID
var provinceID = $("#myProvince").val();
//获取城市
var myCity=$("#myCity");
//加入测试代码
debugger;
$.ajax({
url: "/Province/GetAllCityByProvinceID/" + provinceID,
type: "post",
dataType: "json",
contentType: "application/json",
success: function (result) {
var myHTML = "";
myCity.html("");//赋值之前先清空
$.each(result, function (i, data) {
myHTML += "<option value=" + data.CityID + ">" + data.CityName + "</option>";
});
myCity.append(myHTML);
},
error: function (result) {
alert(result.responseText);
}
});
})
})
</script>
Route：
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Province", action = "Index", id = UrlParameter.Optional }
);
}
