c# - ASP.NET MVC 模型验证不适用于 ViewModel

Question

我有一个 ViewModel，它有一个模型和一些额外的属性。模型上和属性上都有验证，但执行时只检查模型上的验证，属性上的验证被忽略。

模型:

 [MetadataType(typeof(Customer_Validation))]
 public partial class Customer
 {
 }

 public class Customer_Validation
 {
     [Required(ErrorMessage="Please enter your First Name")]
     public string FirstName { get; set; }

     [Required(ErrorMessage = "Please enter your Last name")]
     public string LastName { get; set; }

     [Required(ErrorMessage = "Sorry, e-mail cannot be empty")]
     [Email(ErrorMessage="Invalid e-mail")]
     public string Email { get; set; }
 }

View 模型

 public class RegisterViewModel
 {
     public Customer NewCustomer { get; private set; }

     [Required(ErrorMessage="Required")]
     public string Password { get; private set; }

     public RegisterViewModel(Customer customer, string password)
     {
         NewCustomer = customer;
         Password = password;
     }
 }

Controller

public ActionResult Create()
{
     Customer customer = new Customer();    
     RegisterViewModel model = new RegisterViewModel(customer, "");    
     return View(model);
}

[HttpPost]
public ActionResult Create(Customer newCustomer, string password)
{
     if (ModelState.IsValid)
     {
         try
         {
             // code to save to database, redirect to other page
         }
         catch
         {
             RegisterViewModel model = new RegisterViewModel(newCustomer, password);
             return View(model);
         }
     }
     else
     {
         RegisterViewModel model = new RegisterViewModel(newCustomer, password);
         return View(model);
     }
}

风景

@using (Html.BeginForm())
 {
  <table>
   <tr>
    <td>First Name:</td>
    <td>@Html.TextBoxFor(m => m.NewCustomer.FirstName)</td>
    <td>@Html.ValidationMessageFor(m => m.NewCustomer.FirstName)</td>
   </tr>
   <tr>
    <td>Last Name:</td>
    <td>@Html.TextBoxFor(m => m.NewCustomer.LastName)</td>
    <td>@Html.ValidationMessageFor(m => m.NewCustomer.LastName)</td>
   </tr>
   <tr>
    <td>E-mail:</td>
    <td>@Html.TextBoxFor(m => m.NewCustomer.Email)</td>
    <td>@Html.ValidationMessageFor(m => m.NewCustomer.Email)</td>
   </tr>
   <tr>
    <td>Password:</td>
    <td>@Html.TextBoxFor(m => m.Password)</td>
    <td>@Html.ValidationMessageFor(m => m.Password)</td>
   </tr>
  </table>

  <input type="submit" value="Register" />
 }

如果我提交表单时将密码留空，它就会通过。如果我将客户字段留空，它会显示错误(密码字段除外)

Answer 1

这很正常。您的 POST Controller 操作将 Customer 作为参数而不是 View 模型。验证由模型绑定(bind)器执行，因此当模型绑定(bind)器尝试从请求参数绑定(bind) Customer 对象时，它将调用验证。如果您希望在此 View 模型上执行验证，您的 POST 操作需要将 View 模型作为参数。目前，您在 post 操作中对该 View 模型所做的所有操作都是调用构造函数，而调用构造函数根本不会触发任何验证。

所以你的 POST Action 应该变成:

[HttpPost]
public ActionResult Create(RegisterViewModel newCustomer)
{
     if (ModelState.IsValid)
     {
         // code to save to database, redirect to other page
     }
     else
     {
         return View(newCustomer);
     }
}

请注意您不需要将密码作为第二个操作参数传递，因为它已经是您 View 模型的一部分。