MVC AddModelError 未显示

Question

我查看了this SO post 并按照第一个答案所做的操作，我也做了同样的事情，但我仍然无法看到出现的错误。

模型的相关部分是：

[Display(Name = "Verify13", ResourceType = typeof(Resources.Resource))]
public bool Is13 { get; set; }

控制器是：

if (registerModel.Is13 == false)
{
    ModelState.AddModelError("REGISTER_0", "You must be 13 of age or older to receive email updates.");
    return View(registerModel);
}

视图的部分是：

@Html.ValidationSummary(true)
...
@Html.LabelFor(model => model.Is13)
@Html.CheckBoxFor(model => model.Is13)
@Html.ValidationMessage("REGISTER_O")

我做错了什么？模型的其余部分具有字段属性。整个模型如下图所示。错误消息（必填字段）。除了这个之外，每个错误都会出现。

public class RegisterViewModel
{
    [Display(Name = "FirstName", ResourceType = typeof(Resources.Resource))]
    [Required(ErrorMessageResourceType = typeof(Resources.Resource),
              ErrorMessageResourceName = "FirstNameRequired")]
    [StringLength(50, ErrorMessageResourceType = typeof(Resources.Resource),
                      ErrorMessageResourceName = "FirstNameLong")]
    public string FirstName { get; set; }

    [Display(Name = "LastName", ResourceType = typeof(Resources.Resource))]
    [Required(ErrorMessageResourceType = typeof(Resources.Resource),
              ErrorMessageResourceName = "LastNameRequired")]
    [StringLength(50, ErrorMessageResourceType = typeof(Resources.Resource),
                      ErrorMessageResourceName = "LastNameLong")]
    public string LastName { get; set; }

    [Display(Name = "Email", ResourceType = typeof(Resources.Resource))]
    [Required(ErrorMessageResourceType = typeof(Resources.Resource),
              ErrorMessageResourceName = "EmailRequired")]
    [RegularExpression(".+@.+\\..+", ErrorMessageResourceType = typeof(Resources.Resource),
                                     ErrorMessageResourceName = "EmailInvalid")]
    public string Email { get; set; }

    [Display(Name = "ConfirmEmail", ResourceType = typeof(Resources.Resource))]
    [Required(ErrorMessageResourceType = typeof(Resources.Resource),
            ErrorMessageResourceName = "ConfirmEmailRequired")]
    [RegularExpression(".+@.+\\..+", ErrorMessageResourceType = typeof(Resources.Resource),
                                     ErrorMessageResourceName = "EmailInvalid")]
    public string ConfirmEmailAddress { get; set; }

    [Display(Name = "Password", ResourceType = typeof(Resources.Resource))]
    [Required(ErrorMessageResourceType = typeof(Resources.Resource),
              ErrorMessageResourceName = "PasswordRequired")]
    public string Password { get; set; }

    [Display(Name = "ConfirmPassword", ResourceType = typeof(Resources.Resource))]
    [Required(ErrorMessageResourceType = typeof(Resources.Resource),
              ErrorMessageResourceName = "ConfirmPasswordRequired")]
    public string ConfirmPassword { get; set; }

    [Display(Name = "ZipCode", ResourceType = typeof(Resources.Resource))]
    [Required(ErrorMessageResourceType = typeof(Resources.Resource),
              ErrorMessageResourceName = "ZipCodeRequired")]
    public string ZipCode { get; set; }

    public string[] VideoProvider { get; set; }
    public IEnumerable<SelectListItem> Items { get; set; }

    [Display(Name = "Verify13", ResourceType = typeof(Resources.Resource))]
    public bool Is13 { get; set; }

Answer 1

或者你可以装饰你的财产。

private bool isTrue
{ get { return true; } }

[Required]
[Display(Name = "I agree to the terms and conditions")]
[Compare("isTrue", ErrorMessage = "Please agree to Terms and Conditions")]
public bool iAgree { get; set; }

这是@fields.cage 答案here

这样你的验证逻辑就在它应该在的地方，并且你可以像其他地方一样绑定它。

编辑

在给出我认为你想看到的输出的代码下方。为简单起见，我只实现了 firstname 和 is13 字段。

型号：

public class RegisterViewModel
{
    [Display(Name = "FirstName")]
    [Required]
    public string FirstName { get; set; }

    public bool isTrue
    { get { return true; } }

    [Display(Name = "Verify13")]
    [Required]
    [System.Web.Mvc.CompareAttribute("isTrue", ErrorMessage = "You must be 13 of age or     older to receive email updates.")]
    public bool Is13 { get; set; }
}

查看：

@using (Html.BeginForm("Index", "Home"))
{
    <table>
        <tr>
            <td>@Html.LabelFor(s => s.FirstName)</td>
            <td>@Html.TextBoxFor(s => s.FirstName)</td>
            <td>@Html.ValidationMessageFor(s => s.FirstName)</td>
        </tr>
        <tr>
            <td>@Html.LabelFor(s => s.Is13)</td>
            <td>@Html.CheckBoxFor(s => s.Is13)</td>
            <td>@Html.ValidationMessageFor(s => s.Is13)</td>
        </tr>
    </table>

    <button type="submit">Send</button>
}

控制器：

[HttpPost]
public ActionResult Index(RegisterViewModel model)
{
    if (!ModelState.IsValid)
    {
        return View(model);
    }

    return View(model);
}

Answer 2

您是否将这 2 个 javascript 文件添加到您的视图中（用于客户端验证）：

~/Scripts/jquery.validate.min.js
~/Scripts/jquery.validate.unobtrusive.min.js

如果你使用 Ajax.BeginForm( ) 函数，你还需要这个文件：

~/Scripts/jquery.unobtrusive-ajax.min.js