模型绑定问题

Question

我不清楚为什么这不起作用

public class Regiones
{
    [DisplayName("Select the region")]
    public int SelectedId { get; set; }
    public IEnumerable<SelectListItem> SelectedRegion { get; set; }
    public Regiones()
    {
        SelectedRegion = new[]{
            new SelectListItem { Value = "BR", Text = "Brasil" },
            new SelectListItem { Value = "EUNE", Text = "Europe East" },
            new SelectListItem { Value = "EUW", Text = "Europe West" },
            new SelectListItem { Value = "KR", Text = "Korea" },
            new SelectListItem { Value = "LAN", Text = "Latin America North" },
            new SelectListItem { Value = "LAS", Text = "Latin America South" },
            new SelectListItem { Value = "NA", Text = "Northamerica" },
            new SelectListItem { Value = "OCE", Text = "Oceania" },
            new SelectListItem { Value = "TR", Text = "Tr" },
            new SelectListItem { Value = "PBE", Text = "PBE" },
            new SelectListItem { Value = "Global", Text = "Global" }
        };
    }
}

控制器：

public class FeaturedGamesController : Controller   
{
    public ActionResult Index()
    {
        Regiones region = new Regiones();
        return View(region);
    }

    [HttpPost]
    public ActionResult Featured(Regiones region)
    {
        string selectedregion =             region.SelectedRegion.ElementAt(region.SelectedId).Text;
    }

查看：

<div class="row">
<div class="col-md-12 text-center">
    @using (@Html.BeginForm("Featured", "FeaturedGames", FormMethod.Post, new { id = "form" }))
    {
        @Html.AntiForgeryToken();
        <div class="row">
            <div class="col-md-10 col-md-offset-2">
                <fieldset>
                    <div class="col-md-3">
                        @Html.LabelFor(x => x.SelectedId)
                    </div>

                    <div class="col-md-2">
                        @Html.DropDownListFor(x => x.SelectedId, Model.SelectedRegion, new { @id = "regiones" })
                    </div>

                    <div class="col-md-2">

                        <input type="submit" class="btn btn-default" value="Execute" />
                    </div>
                </fieldset>
            </div>
        </div>

    }
</div>

我试过这个： How to go to particular Item in IEnumerable and this: Pass SelectedValue of DropDownList in Html.BeginForm() in ASP.NEt MVC 3

当我点击发送时，SelectedId 中的结果始终为 0...

我可以缺少什么？提前谢谢你

Answer 1

问题是你的 Value 是 string 类型 SelectListItem 但你的 SelectedId 是 int 类型。

Value 下一行的类型是 string

new SelectListItem { Value = "BR", Text = "Brasil" },

selectedid 下面这行代码是 int.

[DisplayName("Select the region")]
    public int SelectedId { get; set; }

因此，价值在转换中丢失了。将 SelectedId 的数据类型更改为 string 以解决问题。

Fiddle 这里：https://dotnetfiddle.net/SDZZks

模型绑定问题

Issues with ModelBinding

c#

model-view-controller

model-binding

asp.net-mvc-5