模型包含模型列表（MVC-3，Razor）

Question

这个问题已经困扰我两天了。有一些类似的帖子，但没有一个可以完全解决我的问题。

使用 MVC-3，Razor 语法：

-- EDIT.cshtml--

@using (Html.BeginForm("Edit", "My", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
    <!-- Some fields... -->
    <div class="editor-field">
        @Html.TextAreaFor(m => m.LongDescription)
        @Html.ValidationMessageFor(m => m.LongDescription)
    </div>

    <!-- Some more fields work... Including picture upload (summary).-->
    <input name="button" type="submit" value="Add Picture" />

    <!-- Picture Item display -->
    @foreach(var thumbnail in Model.ThumbnailImagePathAndNames) 
    {
      <img src="@Url.Content(@thumbnail.ThumbnailPicturePath)" alt="" width="200" />
      @Html.RadioButtonFor(o=>o.SelectedImage, @thumbnail.ImageGUID)  Primary Picture 
      <!-- Checkbox to mark for deletion -->
      @Html.CheckBoxFor(o=>thumbnail.Delete) Delete ???????? <!---- Here is a problem - I don't understand how this should work -->
    }
    <input id="Submit1" name="button" type="submit" value="Complete Edit!" />
}

-- MyController.cs --

 [HttpPost]
 public ActionResult Edit(String button, HttpPostedFileBase file, MyMainModel model)
 {
     // if button = submit picture,  work with picture here and break(long story)

     // save model data
         // if valid, save and redirect


     // not valid or error, load up view like normal but with error messages
     model.LoadThumbnails();
     return View(model);

 }

-- MyMainModel.cs --

public class MyMainModel
{
    // some properties...
     public Guid? SelectedImage { get; set; }

    [Display(Name = "Detailed Description")]
    public String LongDescription { get; set; }

    // some more properties....


    // and finally my list of models
    public IList<ThumbnailModel> ThumbnailImagePathAndNames { get; set; }

    public void LoadThumbnails()
    {
         // load up initial thumbnail models
         this.ThumbnailImagePathAndNames = new List<ThumbnailModel>(readDataService.GetThumbnailModels(this.SomeID));
    }
}

-- ThumbnailModels.cs --

public class ThumbnailModel
{
    public Guid ImageGUID { get; set; }
    public String FullSizePicturePath { get; set; }
    public String ThumbnailPicturePath { get; set; }

    public bool Delete { get; set; }
}

那么问题是什么？好吧，当“完成编辑！”按下按钮，调用 MyController 的 Edit，正如预期的那样，MyMainModle 的所有数据都完好无损......除了 ThumbnailModel 的列表 - 那些结果为空。

这应该怎么做？我已经尝试了许多不同的方法，包括制作一个可编辑的模板和使用 EditFor(o=>... 都无济于事（这变得令人困惑，因为我不知道 EditFor 是应该用于整个集合还是只是集合中的单个项目 - 我尝试了两种方法）。所有这些都可以正常工作，直到我添加了删除复选框的复杂性，因此需要检索 ThumbnailModels 列表以检查该内部 Delete 属性值。

感谢大家阅读并尝试理解这一点。

[免责声明 - 一些变量和方法名称已被更改以保护无辜程序。很多代码已经被剥离并被注释代码取代。]

Answer 1

这是我用来说明一些概念的示例：

型号：

public class MyMainModel
{
    public Guid? SelectedImage { get; set; }
    public string LongDescription { get; set; }

    public IEnumerable<ThumbnailModel> ThumbnailImagePathAndNames { get; set; }

    public HttpPostedFileBase File { get; set; }
}

public class ThumbnailModel
{
    public Guid ImageGUID { get; set; }
    public bool Delete { get; set; }
}

控制器：

public class HomeController : Controller
{
    public ActionResult Index()
    {
        var model = new MyMainModel
        {
            // TODO: fetch from the repository instead of hardcoding
            ThumbnailImagePathAndNames = new[] 
            {
                new ThumbnailModel { ImageGUID = Guid.NewGuid() },
                new ThumbnailModel { ImageGUID = Guid.NewGuid() },
                new ThumbnailModel { ImageGUID = Guid.NewGuid() },
            }
        };
        return View(model);
    }

    [HttpPost]
    public ActionResult Index(MyMainModel model) 
    {
        ... the model will be properly bound here
    }
}

查看：

@model AppName.Models.MyMainModel
@{
    ViewBag.Title = "Index";
    Layout = "~/Views/Shared/_Layout.cshtml";
}
@using (Html.BeginForm("index", "home", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
    <div class="editor-field">
        @Html.TextAreaFor(m => m.LongDescription)
        @Html.ValidationMessageFor(m => m.LongDescription)
    </div>
    <input type="file" name="file" />
    <!-- Use different names for the upload and complete submit
         buttons so that you can distinguish which one was clicked
         in the POST action 
    -->
    <input name="upload" type="submit" value="Add Picture" />

    @Html.EditorFor(x => x.ThumbnailImagePathAndNames)    
    <input name="complete" type="submit" value="Complete Edit!" />
}

编辑器模板：(~/Views/Home/EditorTemplates/ThumbnailModel.cshtml)：

@model AppName.Models.ThumbnailModel
<!-- Pass the image id as hidden field -->
@Html.HiddenFor(x => x.ImageGUID)
@Html.CheckBoxFor(x => x.Delete)