Question

我正在尝试在MVC3中创建一个多级编辑器。多层次我的意思是我希望能够编辑三个层次结构（父对象，父对象和子子对象集合）的数据。我的模型大致如下：

namespace MvcApplication1.Models
{
    public class Parent
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public Child Child { get; set; }
    }

    public class Child
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public IEnumerable<SubChild> SubChildren { get; set; }    
    }

    public class SubChild
    {
        public int Id { get; set; }
        public string Name { get; set; }
        private DateTime _date = DateTime.Now;
        public DateTime Date { get { return _date; } set { this._date = value; } }
    }
}

由于我想在一个屏幕上显示整个层次结构，因此我创建了以下视图模型：

namespace MvcApplication1.Models.ViewModels
{
    public class ParentViewModel
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public Child Child { get; set; }
        public IEnumerable<SubChild> SubChildren { get { return Child.SubChildren; } set { this.Child.SubChildren = value; } }
    }
}

和控制器看起来像：

    public class ParentController : Controller
    {
        public ActionResult MultiLevelEdit(int id)
        {
            // Simulate data retrieval 
            Parent parent = new Parent { Id = 2 , Name = "P"};
            var child = new Child { Id = 3, Name = "Cild1" };
            List<SubChild> children = new List<SubChild>();
            children.Add(new SubChild { Id = 3, Name = "S1"});
            children.Add(new SubChild { Id = 5, Name = "S 22" });
            child.SubChildren = children;
            parent.Child = child;
            // Create view model
            ParentViewModel vm = new ParentViewModel() { Id = parent.Id, Name = parent.Name, Child = parent.Child, SubChildren = parent.Child.SubChildren };

            return View(vm);
        }

    }

正在呈现的视图是：

@model MvcApplication1.Models.ViewModels.ParentViewModel

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
    <fieldset>

    @Html.HiddenFor(model => model.Id)
    @Html.LabelFor(model => model.Name)
    @Html.EditorFor(model => model.Name)
    <hr />
    Child
    <br />
    @Html.EditorFor(model => model.Child)

    <hr />
    SubChild
    <br />
    @Html.EditorFor(model => model.SubChildren)


    <p>
            <input type="submit" value="Save" />
        </p>
    </fieldset>
}

我在Views \ Shared \ EditorTemplates中创建了两个编辑器模板：

ChildTemplate.cshtml

@model MvcApplication1.Models.Child

@{
    ViewBag.Title = "Child";
}

<h2>Child</h2>

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
    <fieldset>
        <legend>Child</legend>

        @Html.HiddenFor(model => model.Id)

        <div class="editor-label">
            @Html.LabelFor(model => model.Name, "Child Name")
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Name)
            @Html.ValidationMessageFor(model => model.Name)
        </div>
    </fieldset>
}

和SubChildTemplate.cshtml

@model MvcApplication1.Models.SubChild

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
    <fieldset>
        <legend>SubChild</legend>

        @Html.HiddenFor(model => model.Id)

        <div class="editor-label">
            @Html.LabelFor(model => model.Name)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Name)
            @Html.ValidationMessageFor(model => model.Name)
        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.Date)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Date)
            @Html.ValidationMessageFor(model => model.Date)
        </div>
    </fieldset>
}

所有内容都正确呈现，但是当我尝试保存更改时，SubChildren集合为null。我尝试了两种编辑方法的签名：

[HttpPost]
public ActionResult MultiLevelEdit(ParentViewModel parentVM)
{...

[HttpPost]
public ActionResult MultiLevelEdit(ParentViewModel parentVM, FormCollection collection)
{...

并且其中任何一个都没有价值。

任何人都可以建议可以改进哪些方法来完成这项工作？非常感谢。

Answer 1

您的模板未正确命名。应该是：

~/Views/Shared/EditorTemplates/Child.cshtml
~/Views/Shared/EditorTemplates/SubChild.cshtml

此外，我在视图模型上看不到SubChildren属性的用途。

您可以将其删除并显示在主视图中：

@model MvcApplication1.Models.ViewModels.ParentViewModel

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
    <fieldset>

    @Html.HiddenFor(model => model.Id)
    @Html.LabelFor(model => model.Name)
    @Html.EditorFor(model => model.Name)
    <hr />
    Child
    <br />
    @Html.EditorFor(model => model.Child)

    <hr />
    SubChild
    <br />
    @Html.EditorFor(model => model.Child.SubChildren)

    <p>
        <input type="submit" value="Save" />
    </p>
    </fieldset>
}

但是你最大的问题是你有嵌套的HTML <form>元素是不允许的。它是无效的HTML并导致未定义的行为。可能会发布一些值，其他值则不会，...从模板中删除所有Html.BeginForm帮助程序，因为主视图已包含表单。

Answer 2

有关解决方案，请参阅this article。魔术包含在using（Html.BeginCollectionItem（“...”））块中。

简而言之，在使用默认的模型绑定器时，您必须使用正确的字段名称/前缀。

Asp.Net MVC3 Razor - 未从编辑器回发的子项列表

2 个答案: