Question

我有一个包含Product类类型和IEnumerable＆lt;的视图模型。产品＆gt;类型。在帖子上，第一级产品对象从视图模型返回绑定，而产品枚举返回null。

为什么IEnumerable＆lt;选取产品＆GT;每个帖子都没有绑定到我的视图模型？ THX！

型号：

public class Product
{
    public int ID { get; set; }
    public string Name { get; set; }
    public decimal Price { get; set; }
}

public class ProductIndexViewModel
{
    public Product NewProduct { get; set; }
    public IEnumerable<Product> Products { get; set; }
}

public class BoringStoreContext 
{
        public BoringStoreContext()
         {
             Products = new List<Product>();
             Products.Add(new Product() { ID = 1, Name = "Sure", Price = (decimal)(1.10) });
             Products.Add(new Product() { ID = 2, Name = "Sure2", Price = (decimal)(2.10) });
         }
         public List<Product> Products {get; set;}
}

查看：

@model ProductIndexViewModel

@using (@Html.BeginForm())
{
    <div>
        @Html.LabelFor(model => model.NewProduct.Name)
        @Html.EditorFor(model => model.NewProduct.Name)
    </div>
    <div>
        @Html.LabelFor(model => model.NewProduct.Price)
        @Html.EditorFor(model => model.NewProduct.Price)
    </div>
    <div>
        <input type="submit" value="Add Product" />
    </div>

        foreach (var item in Model.Products)
        { 
         <div>
        @Html.LabelFor(model => item.ID)
        @Html.EditorFor(model => item.ID)
    </div>
    <div>
        @Html.LabelFor(model => item.Name)
        @Html.EditorFor(model => item.Name)
    </div>
    <div>
        @Html.LabelFor(model => item.Price)
        @Html.EditorFor(model => item.Price)
    </div>

        }
       }

控制器：

public class HomeController : Controller
{
    BoringStoreContext db = new BoringStoreContext();

    public ActionResult Index()
    {
        ProductIndexViewModel viewModel = new ProductIndexViewModel
        {
            NewProduct = new Product(),
            Products = db.Products
        };
        return View(viewModel);
    }

    [HttpPost]
    public ActionResult Index(ProductIndexViewModel viewModel)
    {
        // ???? viewModel.Products is NULL here
        // ???? viewModel.NewProduct comes back fine

        return View();
    }

Answer 1

您没有正确使用lambda表达式。您需要通过模型访问“产品”列表。尝试这样做：

@count = 0
foreach (var item in Model.Products)
    { 
     <div>
    @Html.LabelFor(model => model.Products[count].ID)
    @Html.EditorFor(model => model.Products[count].ID)
</div>
<div>
    @Html.LabelFor(model => model.Products[count].Name)
    @Html.EditorFor(model => model.Products[count].Name)
</div>
<div>
    @Html.LabelFor(model => model.Products[count].Price)
    @Html.EditorFor(model => model.Products[count].Price)
</div>
@count++
    }

修改

控制器：

BoringStoreContext db = new BoringStoreContext(); public ActionResult Index() { ProductIndexViewModel viewModel = new ProductIndexViewModel { NewProduct = new Product(), Products = db.Products }; return View(viewModel); } [HttpPost] public ActionResult Index(ProductIndexViewModel viewModel) { // work with view model return View(); }

模型

public class Product { public int ID { get; set; } public string Name { get; set; } public decimal Price { get; set; } } public class ProductIndexViewModel { public Product NewProduct { get; set; } public List<Product> Products { get; set; } } public class BoringStoreContext { public BoringStoreContext() { Products = new List<Product>(); Products.Add(new Product() { ID = 1, Name = "Sure", Price = (decimal)(1.10) }); Products.Add(new Product() { ID = 2, Name = "Sure2", Price = (decimal)(2.10) }); } public List<Product> Products { get; set; } }

查看：

@model Models.ProductIndexViewModel @using (@Html.BeginForm()) { <div> @Html.LabelFor(model => model.NewProduct.Name) @Html.EditorFor(model => model.NewProduct.Name) </div> <div> @Html.LabelFor(model => model.NewProduct.Price) @Html.EditorFor(model => model.NewProduct.Price) </div> for (int count = 0; count < Model.Products.Count; count++ ) { <div> @Html.LabelFor(model => model.Products[count].ID) @Html.EditorFor(model => model.Products[count].ID) </div> <div> @Html.LabelFor(model => model.Products[count].Name) @Html.EditorFor(model => model.Products[count].Name) </div> <div> @Html.LabelFor(model => model.Products[count].Price) @Html.EditorFor(model => model.Products[count].Price) </div> } <div> <input type="submit" value="Add Product" /> </div> }

Answer 2

Travis's answer将解决此问题。这是使用EditorTemplates

的另一种方法

您可以使用Editor template来显示产品，它可以正常使用。

1）在Views / Home文件夹下创建名为“EditorTemplates”的文件夹

2）在其中添加名为“Products”的视图。将此代码添加到该视图

@model SO_MVC.Models.Product
@{
   Layout = null;
}
<p>
  @Html.LabelFor(x=>x.ID)
  @Html.EditorFor(x=>x.ID) 
</p>
<p>
  @Html.LabelFor(x=>x.Name)
  @Html.EditorFor(x=>x.Name)
</p>
<p>
  @Html.LabelFor(x=>x.Price)
  @Html.EditorFor(x=>x.Price)
</p> 
@Html.HiddenFor(x=>x.Id)

在主视图中，您可以像这样调用此编辑器模板

  @Html.EditorFor(m=>m.Products)

查看模型IEnumerable＆lt;＆gt;属性从post方法返回null（不绑定）？

2 个答案: