查看和从第三方实体拉取说明的“一多列表”框

尝试使用以下视图模型并从控制器填充 TypeEvents

public class EventViewModel
{
    public int Id {get;set;}
    public string Description {get;set;}
    public int TypeEventId    
    public IEnumerable<TypeEvent> TypeEvents {get;set;}
}

public class YourController
{
    [HttpGet]
    public ActionResult CreateEvent()
    {
        var viewModel = new EventViewModel();
        viewModel.TypeEvents = ... // fill Data for DropDownList here
        return View(viewModel);
    }
    [HttpPost]
    public ActionResult CreateEvent(EventViewModel viewModel)
    {
         // You should have all the data you need in the viewModel
    }
}

然后在视图中：

 @Html.DropDownListFor(m => m.TypeEventId, new SelectList(Model.TypeEvents,"Id","Description") )

控制器的 POST 操作应执行数据库/业务逻辑调用

如果您希望能够一次添加多个类型事件，则必须以不同的方式执行此操作...例如，使用字典创建一个存储库，其中 GUID 作为键，并将此 Guid 添加到视图模型中。再创建 2 个控制器发布操作，一个用于添加新的事件类型，另一个用于删除它。显示附加了哪些 EventType 的部分应该放在部分视图中，该视图填充了 2 个操作并重新发送到客户端。我最近不得不这样做，它看起来像这样：

@model Apps4KidsWeb.Models.AddAppViewModel
@using Apps4KidsWeb.Domain
<table>
    @foreach (KeyValuePair<int, int> item in Model.OperatingSystems)
    {
        <tr>
            <td>@operatingSystems[item.Value]</td>
            <td>
                @Ajax.ActionLink(
                                        "Remove",
                                        "RemoveOperatingSystem",
                                        "Admin",
                                        new { guid = Model.Guid, id = item.Key },
                                        new AjaxOptions
                                        {
                                            HttpMethod = "POST",
                                            InsertionMode = InsertionMode.Replace,
                                            UpdateTargetId = "operatingSystems"
                                        })</td>
        </tr>
    }
</table>

和包含视图：

@model Apps4KidsWeb.Models.AddAppViewModel
@{
    ViewBag.Title = "Add App";
    ViewBag.CurrentPage = "Add App";
}
<div class="float">
    <h3>Categories</h3>
    <div id="categories">
        @Html.Partial("_Categories", Model)
    </div>

    @using (Ajax.BeginForm("AddCategory", "Admin",
    new AjaxOptions() { HttpMethod = "POST", UpdateTargetId = "categories", InsertionMode = InsertionMode.Replace }))
    {
        @Html.HiddenFor(model => model.Guid)
        @Html.EditorFor(model => model.Category)
        <input type="submit" value="Add" />    
    }
</div>
<div class="float">
    <h3>Operating Systems</h3>
    <div id="operatingSystems">
        @Html.Partial("_OperatingSystems", Model)
    </div>
    @using (Ajax.BeginForm("AddOperatingSystem", "Admin",
    new AjaxOptions() { HttpMethod = "POST", UpdateTargetId = "operatingSystems", InsertionMode = InsertionMode.Replace }))
    {
        @Html.HiddenFor(model => model.Guid)
        @Html.EditorFor(model => model.OS)
        <input type="submit" value="Add" />  
    }
</div>
<div class="clear"></div>
@using (Html.BeginForm("AddApp", "Admin"))
{
    @Html.AntiForgeryToken()
    @Html.ValidationSummary(true)
    @Html.HiddenFor(model => model.Guid)
    @Html.EditorForModel()
    <p>
        <input type="submit" value="Weiter" />
    </p>
}

@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}

控制器：

    /// <summary>
    /// Adds an operating system to the AddAppViewModel
    /// </summary>
    /// <param name="Guid">The Guid of the item</param>
    /// <param name="OS">The id of the operating system</param>
    /// <returns>PartialView _OperatingSystems</returns>
    [HttpPost]
    public ActionResult AddOperatingSystem(string Guid, int OS)
    {
        var viewmodel = EditedAppRepository.GetInstance().GetApp(Guid);
        viewmodel.AddOperatingSystem(OS);
        return PartialView("_OperatingSystems", viewmodel);
    }
    /// <summary>
    /// Removes an operating sytem from the AddAppViewModel
    /// </summary>
    /// <param name="Guid">The Guid of the item</param>
    /// <param name="id">The id of the operating system</param>
    /// <returns></returns>
    [HttpPost]
    public ActionResult RemoveOperatingSystem(string Guid, int id)
    {
        var viewmodel = EditedAppRepository.GetInstance().GetApp(Guid);
        viewmodel.RemoveOperatingSystem(id);
        return PartialView("_OperatingSystems", viewmodel);
    }

和存储库：

using Apps4KidsWeb.Domain;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace Apps4KidsWeb.Models
{
    public class EditedAppRepository
    {
        #region singleton
        private static EditedAppRepository singleton;
        public static EditedAppRepository GetInstance()
        {
            if (singleton == null)
            {
                singleton = new EditedAppRepository();                
            }
            return singleton;
        }
        private EditedAppRepository()
        {
            this.repository = new Dictionary<string, AddAppViewModel>();
        }
        #endregion
        #region fields
        private Dictionary<string, AddAppViewModel> repository;
        #endregion
        #region methods
        public AddAppViewModel CreateNewApp(IApp app)
        {
            string guid = Guid.NewGuid().ToString();
            AddAppViewModel result = new AddAppViewModel(app) { Guid = guid };
            repository.Add(guid, result);
            result.Saved += OnAppSaved;
            return result;
        }
        public AddAppViewModel CreateNewApp(IRecommendationEx recommendation) 
        {
            string guid = Guid.NewGuid().ToString();
            AddAppViewModel result = new AddAppViewModel(recommendation) { Guid = guid };
            repository.Add(guid, result);
            result.Saved += OnAppSaved;
            return result;
        }
        public AddAppViewModel CreateNewApp()
        {
            string guid = Guid.NewGuid().ToString();
            AddAppViewModel result = new AddAppViewModel() { Guid=guid  };
            repository.Add(guid, result);
            result.Saved += OnAppSaved;
            return result;
        }
        public AddAppViewModel GetApp(string guid)
        {
            if (guid != null && repository.ContainsKey(guid))
            {
                return repository[guid];
            }
            return null;
        }
        private void OnAppSaved(object sender, EventArgs e)
        {
            AddAppViewModel model = (AddAppViewModel)sender;
            repository.Remove(model.Guid);
        }
        public byte[] GetAppPicture(string guid, int id)
        {
            return repository[guid].Images[id];
        }
        #endregion
    }
}