Question

我正在尝试将用户从下拉列表“COUNTRY”中选择的值从视图传递到控制器，我尝试通过HTTP POST方法检索它并且我没有成功。以下是我的观点代码：

@using WebApplication1.Models
@using WebApplication1.Controllers
@model Country

@{
    ViewBag.Title = "Index";
}

@using (Html.BeginForm())
{
    <h2>Airport List</h2>
    @Html.Label("Airports", "Airports")
    <select name="Airports">
        @foreach (var airport in ViewBag.EuropeanAirports)
        {
            <option value="@(airport.name)">@(airport.name)</option>
        }
    </select>

    @Html.Label("Country", "Country")


    @Html.DropDownListFor(c =>c.country, new SelectList(ViewBag.countries, 
  "country", "country"), "Select Country")

}

这是我的控制器：

public class AirportController : Controller
{
    // GET: HelloWorld
    public ActionResult Create()
    {
        IEnumerable<Airport> airports = GetAirports();
        //LINQ QUERY TO RETRIEVE ALL EUROPEAN AIRPORTS 
        IEnumerable<Airport> EuropeanAirports = from n in airports
                       where n.continent.Equals("EU")
                       select n;
        IEnumerable<Country> countries = GetCountries();
        ViewBag.countries = countries;
        ViewBag.EuropeanAirports = EuropeanAirports; 
        return View(new Country());
    }

这是我的国家模型：

public class Country
{
    public string country { get; set; }
    public string abbr { get; set; }
}

我的目标是再次检索用户从国家/地区下拉列表中选择的值。我不知道是否应该为create添加post方法，我不知道如何将所选值从视图传递给控制器。

Answer 1

默认情况下，Html Helper表单将发布到同一个控制器操作。您可以使用HttpPost方法属性声明它，如此

[HttpPost]
public ActionResult Create(Country postedCountry)
{

    string selectedCountry = postedCountry.country

}

如您所见，发布的对象将与您传递给视图的模型相同，其属性将由用户发布的表单选择确定

Answer 2

  [HttpGet]
  public ActionResult Create()
    {
        IEnumerable<Airport> airports = GetAirports();
        //LINQ QUERY TO RETRIEVE ALL EUROPEAN AIRPORTS 
        IEnumerable<Airport> EuropeanAirports = from n in airports
                       where n.continent.Equals("EU")
                       select n;
        IEnumerable<Country> countries = GetCountries();
        ViewBag.countries = countries;
        ViewBag.EuropeanAirports = EuropeanAirports; 
        return View(new Country());
    }

发布的名称是您的模型中拼写的国家/地区

[HttpPost]
    public ActionResult Create(string country)
        {
         if (ModelState.IsValid)//if theres not errors
            {
               //Add your save Funcation Here
               //db.Countries.Add(country)
                db.SaveChanges();
                return RedirectToAction("Index");
            }
            return View();//if there is errors display the same view
        }

如果您需要保存Airport ddl 只需将ddl的名称添加到控制器就像这样

 public ActionResult Create(string country,string Airports)

希望这个帮助！

将下拉列表中选择的值从视图传递到控制器

2 个答案: