Question

假设您有以下对象：

public class Address
{
  public String Line1 { get; set; }
  public String Line2 { get; set; }
  public String City { get; set; }
  public String State { get; set; }
  public String ZipCode { get; set; }

  public Address()
  {
  }
}

public class Contact
{
  public String FirstName { get; set; }
  public String LastName { get; set; }
  public String Telephone { get; set; }

  public Address BillingAddress { get; set; }
  public List<Address> ShippingAddresses { get; set; }

  public Contact()
  {
    // Assume anything that _could_ be null wouldn't be. I'm excluding
    // most "typical" error checking just to keep the examples simple
    this.BillingAddress = new Address();
    this.ShippingAddresses = new List<Address>();
  }
}

假设使用[Required]，[Display]和其他属性修饰属性。

然后是我的控制器（为了演示而简化）：

public ActionResult Edit(String id)
{
  Contact contact = ContactManager.FindByID(id);
  return View(model: contact);
}

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Edit(Contact contact)
{
  if (ModelState.IsValid) //always fails
  {
    ContactManager.Save(contact);
    return RedirectToAction("Saved");
  }
  return View(model: contact);
}

我一直看到在MVC中编辑像这样的对象的演示，但他们不断地将对象的集合分解为他们自己的形式（例如编辑联系人，然后编辑联系人的特定地址）。另一方面，我试图在同一页面内编辑所有这些信息，但没有成功。例如：

@model Contact

// simplified for brevity
@using (Html.BeginForm())
{
  @Html.LabelFor(x => x.FirstName): @Html.EditorFor(x => x.FirstName)
  @Html.LabelFor(x => x.LastName): @Html.EditorFor(x => x.LastName)
  @Html.LabelFor(x => x.Telephone): @Html.EditorFor(x => x.Telephone)

  <div>
    @Html.LabelFor(x => x.BillingAddress.Line1): @Html.EditorFor(x => x.BillingAddress.Line1)
    @Html.LabelFor(x => x.BillingAddress.Line2): @Html.EditorFor(x => x.BillingAddress.Line2)
    @Html.LabelFor(x => x.BillingAddress.City): @Html.EditorFor(x => x.BillingAddress.City)
    @Html.LabelFor(x => x.BillingAddress.State): @Html.EditorFor(x => x.BillingAddress.State)
    @Html.LabelFor(x => x.BillingAddress.ZipCode): @Html.EditorFor(x => x.BillingAddress.ZipCode)
  </div>

  <div>
  @foreach (Address addr in Model.ShippingAddresses)
  {
    <div>
      @Html.LabelFor(x => addr.Line1): @Html.EditorFor(x => addr.Line1)
      @Html.LabelFor(x => addr.Line2): @Html.EditorFor(x => addr.Line2)
      @Html.LabelFor(x => addr.City): @Html.EditorFor(x => addr.City)
      @Html.LabelFor(x => addr.State): @Html.EditorFor(x => addr.State)
      @Html.LabelFor(x => addr.ZipCode): @Html.EditorFor(x => addr.ZipCode)
    </div>
  }
  </div>
}

我一直在遇到的问题是，当我去保存信息时，ModelState.IsValid永远不会通过。这样做有诀窍，还是仅仅在MVC之外？我想带一个像Contact这样的对象并将所有信息转储到一个页面上进行编辑，并让它重新保存成功，但我似乎无法让它工作。（我的下一步是绑定ajax，以便您可以在该页面上动态添加/删除“ShipingAddresses”，但我需要首先保存 - K.I.S.S）

问题：

ModelState.IsValid几乎总是假的
集合项的表单元素通常具有相同的名称，因此在此演示中，Line1集合中的每个ShippingAddresses都会转储到页面name="addr_Line1"，而不是ShippingAddresses[0]_Line1就像我期待的那样。

Answer 1

我猜ModelState.IsValid是错误的，因为您没有正确填充送货地址集合。发生这种情况是因为您没有为输入字段使用专有名称。查看following article以更好地理解模型绑定器期望命名输入字段的格式，以便能够重新构建值。

您的代码未生成正确的输入名称的原因是您使用了此视图丢失了导航上下文跟踪的foreach循环。

所以试试这样：

@for (var i = 0; i < Model.ShippingAddresses.Count; i++)
{
    <div>
        @Html.LabelFor(x => x.ShippingAddresses[i].Line1): 
        @Html.EditorFor(x => x.ShippingAddresses[i].Line1)

        @Html.LabelFor(x => x.ShippingAddresses[i].Line2): 
        @Html.EditorFor(x => x.ShippingAddresses[i].Line2)

        @Html.LabelFor(x => x.ShippingAddresses[i].City): 
        @Html.EditorFor(x => x.ShippingAddresses[i].City)

        @Html.LabelFor(x => x.ShippingAddresses[i].State): 
        @Html.EditorFor(x => x.ShippingAddresses[i].State)

        @Html.LabelFor(x => x.ShippingAddresses[i].ZipCode): 
        @Html.EditorFor(x => x.ShippingAddresses[i].ZipCode)
    </div>    
}

备注：请注意，我还使用EditorFor调用替换了您的重复标签，以有效地为这些字段生成输入字段。

甚至更好地使用这样的编辑器模板：

@model Contact

@using (Html.BeginForm())
{
    @Html.LabelFor(x => x.FirstName): 
    @Html.EditorFor(x => x.FirstName)

    @Html.LabelFor(x => x.LastName): 
    @Html.EditorFor(x => x.LastName)

    @Html.LabelFor(x => x.Telephone): 
    @Html.EditorFor(x => x.Telephone)

    @Html.EditorFor(x => x.BillingAddress)

    @Html.EditorFor(x => x.ShippingAddresses)
}

然后定义一个自定义编辑器模板，该模板将自动为ShippingAddresses集合（~/Views/Shared/EditorTemplates/Address.cshtml）的每个元素呈现：

@model Address
<div>
    @Html.LabelFor(x => x.Line1): 
    @Html.EditorFor(x => x.Line1)

    @Html.LabelFor(x => x.Line2): 
    @Html.EditorFor(x => x.Line2)

    @Html.LabelFor(x => x.City): 
    @Html.EditorFor(x => x.City)

    @Html.LabelFor(x => x.State): 
    @Html.EditorFor(x => x.State)

    @Html.LabelFor(x => x.ZipCode): 
    @Html.EditorFor(x => x.ZipCode)
</div>

现在您不再担心输入错误的输入名称。不仅如此，您还要重复使用地址编辑器模板来计算帐单地址和送货地址。它使您的观点更加清晰。

编辑和保存复杂对象

1 个答案: