带有实体数据模型的自定义验证 MVC 3

Question

我正在使用 MVC3 开发一个项目。我首先创建了一个数据库（具有必要的约束，如 PK 和 FK），并使用 ADO.NET 实体数据模型将此数据库添加到我的 webappplicatie。一切似乎都很好，但我不能让验证变得灵活。这里有一些代码可以澄清我的问题。

---

编辑：添加了视图 + 正确的模型。此版本不导入数据库，但结果相同。

---

--型号----

namespace CustomValidation.Models
{
    public class Person : IValidatableObject
    {   

    public int Id { get; set; }
    [Required]
    public String FirstName { get; set; }
    [Required]
    public String LastName { get; set; }

    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        if (String.IsNullOrEmpty(FirstName))
        {
            var field = new[] { "FirstName" };
            yield return new ValidationResult("Firstname can't be null", field);
        }
    }
}
}



namespace CustomValidation.Models
{
    public class Address : IValidatableObject
    {

    public int Id { get; set; }
    [Required]
    public String Streetname { get; set; }
    [Required]
    public String Zipcode { get; set; }
    [Required]
    public String City { get; set; }
    [Required]
    public String Country { get; set; }
    public Person Person { get; set; }

    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        if (String.IsNullOrEmpty(Streetname))
        {
            var field = new[] { "Streetname" };
            yield return new ValidationResult("Streetname can't be null", field);
        }
    }
}
}


public class MasterModel
{
    public List<Address> Addressess { get; set; }
    public Person Person { get; set; }
    }
}





namespace CustomValidation.Models
{
    public class DBEntities : DbContext
    {
    public DbSet<Person> People { get; set; }
    public DbSet<Address> Addressess { get; set; }
    }
}

----控制器----

namespace CustomValidation.Controllers
{
public class HomeController : Controller
{
    public ActionResult Index()
    {
        MasterModel Model = new MasterModel();
        Model.Person = new Person();
        Model.Addressess = new List<Address>();
        Model.Addressess.Add(new Address());
        Model.Addressess.Add(new Address());
        return View(Model);
    }


    [HttpPost]
    public ActionResult Index(MasterModel Model)
    {
        DBEntities _db = new DBEntities();
        if (TryValidateModel(Model.Person))
        {
            _db.People.Add(Model.Person);
            _db.SaveChanges();
        }
        else
        {
            return View(Model);
        }

        for (int i = 0; i < Model.Addressess.Count; i++)
        {
            if (!String.IsNullOrEmpty(Model.Addressess[i].Country))
            {
                if (TryValidateModel(Model.Addressess[i]))
                {
                    Model.Addressess[i].Person = Model.Person;
                    _db.Addressess.Add(Model.Addressess[i]);
                    _db.SaveChanges();
                }
                else
                {
                    return View(Model);
                }
            }
        }
        return RedirectToAction("Index");
    }
 }

这是我的观点：

@model CustomValidation.Models.MasterModel
@{
ViewBag.Title = "Index";
}

<h2>Create</h2>

@using (Html.BeginForm()) {
@Html.ValidationSummary(true)
<fieldset>
<legend>Person</legend>
<div class="editor-label">
@Html.LabelFor(m => Model.Person.FirstName)
@Html.EditorFor(m => Model.Person.FirstName)
</div>
<div class="editor-label">
@Html.LabelFor(m => Model.Person.LastName)
@Html.EditorFor(m => Model.Person.LastName)
</div>

</fieldset>
for (int i = 0; i < Model.Addressess.Count; i++)
{
<fieldset>
    <legend>Address</legend>

    <div class="editor-label">
        @Html.LabelFor(model => Model.Addressess[i].Streetname)
    </div>
    <div class="editor-field">
        @Html.EditorFor(model => model.Addressess[i].Streetname)
        @Html.ValidationMessageFor(model => Model.Addressess[i].Streetname)
    </div>

    <div class="editor-label">
        @Html.LabelFor(model => Model.Addressess[i].Zipcode)
    </div>
    <div class="editor-field">
        @Html.EditorFor(model => Model.Addressess[i].Zipcode)
        @Html.ValidationMessageFor(model => Model.Addressess[i].Zipcode)
    </div>

    <div class="editor-label">
        @Html.LabelFor(model => Model.Addressess[i].City)
    </div>
    <div class="editor-field">
        @Html.EditorFor(model => Model.Addressess[i].City)
        @Html.ValidationMessageFor(model => Model.Addressess[i].City)
    </div>

    <div class="editor-label">
        @Html.LabelFor(model => Model.Addressess[i].Country)
    </div>
    <div class="editor-field">
        @Html.EditorFor(model => Model.Addressess[i].Country)
        @Html.ValidationMessageFor(model => Model.Addressess[i].Country)
    </div>

</fieldset>

}
    <p>
        <input type="submit" value="Create" />
    </p>
}

问题（我在调试类似的东西时注意到）是在请求进入我的操作之前，MVC 首先为您的集合运行验证器。因此，如果我只在表单中填写了 Person，而在验证 Model.Person 时它只会返回 false（我猜是因为 Address 的必填字段），所以它会反弹回我的视图。

我需要一些解决方法，让我决定要在我的操作中验证我的集合的哪些实例。

在网上找了很久也没找到解决办法。

希望有人能帮帮我。

PS。我是 Visual Studio 和 MVC 3 的新手，所以请不要对我太苛刻:)

Answer 1

为了验证返回给您的操作的模型的子模型，您需要将TryValidateModel 应用于特定的子模型，并使用包含模型前缀的重载。如果查看生成的 HTML，您将看到 Person 字段以 Person 作为前缀，第一个 Address 字段以 Addressess[0] 作为前缀，第二个 Address 字段以 Addressess[1] 作为前缀。

另外，在调用 TryValidateModel 之前必须清除所有模型错误（否则现有错误会导致 TryValidateModel 返回 false）。

执行以下操作：

[HttpPost]
public ActionResult Index(MasterModel model)
{
    var reloadView = true;

    // clear any existing errors
    foreach (var key in ModelState.Keys)
        ModelState[key].Errors.Clear();

    if (TryValidateModel(model.Person, "Person"))   
    {   
        _db.People.Add(model.Person);   
        _db.SaveChanges();   
        reloadView = false;

        for (var i = 0; i < model.Addressess.Count(); i++)
        {
            foreach (var key in ModelState.Keys)
                ModelState[key].Errors.Clear();

            if (TryValidateModel(model.Addressess[i], "Addressess[" + i.ToString() + "]"))
            {
                **// UPDATED CODE**
                // add Person to Address model
                model.Addressess[i].Person = model.Person;

                _db.Addressess.Add(model.Addressess[i]);   
                _db.SaveChanges();   
            }
        }
    }

    if (reloadView)
    {
        // clear and re-add all errors
        foreach (var key in ModelState.Keys)
            ModelState[key].Errors.Clear();

        TryValidateModel(model);
        return View(model);
    }
    else
    {
        // go to some other view
    }
}