Question

我是.NET MVC的初学者，并尝试执行一项简单的任务，例如在下拉列表中显示项目列表。但是，我当前的代码会生成一个下拉列表，显示项目类型的名称而不是实际值。谢谢你的帮助。：）

DropDown not displaying the correct values

我的代码如下;

SelectArticleModel.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace TheMakingOfAWebApplication.Models
{
    public class SelectArticleModel
    {
        public string Name { get; set; }
        public IEnumerable<Article> Articles { get; set; }
    }
}

Article.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace TheMakingOfAWebApplication.Models
{
    public class Article
    {
        public string Name { get; set; }
    }
}

HomeController.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using TheMakingOfAWebApplication.Models;

namespace TheMakingOfAWebApplication.Controllers
{
    public class HomeController : Controller
    {
        // GET: Home
        public ActionResult Index()
        {
            //List<Article> articles;

            SelectArticleModel model = new SelectArticleModel();
            model.Name = "";
            model.Articles = new List<Article>{
                new Article { Name = "Bananas"},
                new Article { Name = "Apples"},
                new Article { Name = "Oranges"},
                new Article { Name = "Melons"},
                new Article { Name = "Grapes"},
                new Article { Name = "Sallad"},
                new Article { Name = "Potatoes"},
                new Article { Name = "Cucumber"},
                new Article { Name = "Beans"},
                new Article { Name = "Tomatoes"}
            };
            return View(model);
        }
    }
}

Index.cshtml

@model TheMakingOfAWebApplication.Models.SelectArticleModel

@{
    ViewBag.Title = "Index";
}

<h2>Index</h2>

@using (Html.BeginForm())
{
    @Html.AntiForgeryToken()

    <div class="form-horizontal">
        <h4>Article</h4>
        <hr />
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })
        <div class="form-group">
            @Html.LabelFor(model => model.Name, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.DropDownListFor(m => m.Name, new SelectList(Model.Articles))) 
                @Html.ValidationMessageFor(model => model.Name, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            <div class="col-md-offset-2 col-md-10">
                <input type="submit" value="Save" class="btn btn-default" />
            </div>
        </div>
    </div>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>

Answer 1

让您的SelectList知道Value和Text属性名称是什么。

@Html.DropDownListFor(m => m.Name, 
                 new SelectList(Model.Articles, "Name", "Name", Model.Name)))

Answer 2

由于您使用复杂对象进行绑定，因此可以将dataTextField和dataValueField指定为SelectList的参数。请尝试以下方法：

@Html.DropDownListFor(m => m.Name, new SelectList(Model.Articles,"Name","Name"))

如果你有一个像字符串这样的基本类型的列表，那么你正在使用的SelectList的重载可以在不提及额外参数的情况下工作。

为什么@ Html.DropDownListFor（）中没有显示正确的值？

2 个答案: