复合视图模型和更新模型

Question

缺少在POST操作中的未填充值中恢复的缺陷？

控制器

public ActionResult Index() 
{ 
    var productPageViewModel = new ProductPageViewModel(); 

    productPageViewModel.ProductPageCriteria = BuildProductPageCriteriaViewModel(); 
    productPageViewModel.Products = GetProducts(productPageViewModel.ProductPageCriteria); 

    return View(productPageViewModel); 
} 

[HttpPost] 
public ActionResult Index(ProductPageViewModel productPageViewModel, FormCollection formCollection) 
{ 
    // productPageViewModel is not populated with posted values of ProductPageCriteria.CategoryID, ProductPageCriteria.DepartmentID and ProductPageCriteria.PageSize 
    // formCollection has correct values 
    // Calling UpdateModel(productPageViewModel); has no affect - makes sense, the framework has already called it 
    // Calling UpdateModel(productPageViewModel.ProductPageCriteria); populates the values. 
    // The renderd form has names like CategoryID, DepartmentID unlike ProductPageCriteria.CategoryID, ProductPageCriteria.DepartmentID 
    //  if the top model was passed to all partial views also. 

    return View(productPageViewModel); 
} 

模型

public class ProductPageCriteriaViewModel 
{ 
    public const int DefaultPageSize = 15; 

    public ProductPageCriteriaViewModel() 
    { 
     Categories = new List<Category>(); 
     Departments = new List<Department>(); 

     PageSize = DefaultPageSize; 
    } 

    [Display(Name = "Category")] 
    public int? CategoryID { get; set; } 
    [Display(Name = "Department")] 
    public int DepartmentID { get; set; } 
    [Display(Name = "Page Size")] 
    public int? PageSize { get; set; } 

    public List<Category> Categories { get; set; } 
    public List<Department> Departments { get; set; } 
} 

public class ProductPageViewModel 
{ 
    public ProductPageViewModel() 
    { 
     ProductPageCriteria = new ProductPageCriteriaViewModel(); 
     Products = new List<Product>(); 
    } 

    public ProductPageCriteriaViewModel ProductPageCriteria { get; set; } 
    public List<Product> Products { get; set; } 
} 

public class Product 
{ 
    public int ProductID { get; set; } 
    public string ProductName { get; set; } 

    public Category Category { get; set; } 
    public Department Department { get; set; } 
} 

public class Category 
{ 
    public int CategoryID { get; set; } 
    public string CategoryName { get; set; } 
} 

public class Department 
{ 
    public int DepartmentID { get; set; } 
    public string DepartmentName { get; set; } 
} 

查看Index.cshtml

@using (Html.BeginForm()) { 
    @Html.ValidationSummary(true) 

    @Html.Partial("_ProductCriteria", Model.ProductPageCriteria) 

    @Html.Partial("_ProductList", Model.Products) 
} 

管窥_ProductCriteria.cshtml

@model Mvc3Application4.Models.ProductPageCriteriaViewModel 

<fieldset> 
    <legend>Criteria</legend> 

    <div class="editor-label"> 
     @Html.LabelFor(model => model.CategoryID) 
    </div> 
    <div class="editor-field"> 
     @Html.DropDownListFor(model => model.CategoryID, new SelectList(Model.Categories, "CategoryID", "CategoryName", Model.CategoryID), "--- All ---") 
     @Html.ValidationMessageFor(model => model.CategoryID) 
    </div> 

    <div class="editor-label"> 
     @Html.LabelFor(model => model.DepartmentID) 
    </div> 
    <div class="editor-field"> 
     @Html.DropDownListFor(model => model.DepartmentID, new SelectList(Model.Departments, "DepartmentID", "DepartmentName", Model.DepartmentID), "--- All ---") 
     @Html.ValidationMessageFor(model => model.DepartmentID) 
    </div> 

    <div class="editor-label"> 
     @Html.LabelFor(model => model.PageSize) 
    </div> 
    <div class="editor-field"> 
     @Html.DropDownListFor(model => model.PageSize, new SelectList(new List<int> {10, 15, 20, 25, 50, 100}.Select(n => new {Value = n, Text = n}), "Value", "Text", Model.PageSize), "--- All ---") 
     @Html.ValidationMessageFor(model => model.PageSize) 
    </div> 

    <p> 
     <input type="submit" value="Search" /> 
    </p> 
</fieldset> 

局部视图_ProductList.cshtml

@model IEnumerable<Mvc3Application4.Models.Product> 

<p> 
    @Html.ActionLink("Create New", "Create") 
</p> 
<table> 
    <tr> 
     <th></th> 
     <th> 
      ProductName 
     </th> 
    </tr> 

@foreach (var item in Model) { 
    <tr> 
     <td> 
      @Html.ActionLink("Edit", "Edit", new { id=item.ProductID }) | 
      @Html.ActionLink("Details", "Details", new { id=item.ProductID }) | 
      @Html.ActionLink("Delete", "Delete", new { id=item.ProductID }) 
     </td> 
     <td> 
      @item.ProductName 
     </td> 
    </tr> 
} 

</table> 

Answer 1

这是我的头和未经考验的顶部，但我相信，如果你通过父模型（ProductPageViewModel）的产品标准局部视图，改变局部视图继承此模型，并更改要使用的控件model => model.ProductPageCriteria.CategoryID而不是model => model.CategoryID，它应该保持命名，以便UpdateModel可以使用发布的值匹配字段。

对不起，对于极端的磨合句，如果这是不正确的，我相信我会很快赢得我的Peer Pressure徽章。 ：） 希望这可以帮助。