用于检查我的模型属性中的重复项的自定义验证属性未触发

Question

我想向我的模型添加自定义验证属性以检查是否有任何答案包含重复项。也就是说，如果用户在任何字段中键入相同的答案，我想在他们键入重复答案时显示错误。

这是我的模型：

public class SecurityQuestions
{
    public int Question1Id { get; set; }
    public int Question2Id { get; set; }
    public int Question3Id { get; set; }
    public int Question4Id { get; set; }
    public int Question5Id { get; set; }
    public int Question6Id { get; set; }

    [UniqueAnswersOnly]
    public string Answer1 { get; set; }
    [UniqueAnswersOnly]
    public string Answer2 { get; set; }
    [UniqueAnswersOnly]
    public string Answer3 { get; set; }
    [UniqueAnswersOnly]
    public string Answer4 { get; set; }
    [UniqueAnswersOnly]
    public string Answer5 { get; set; }
    [UniqueAnswersOnly]
    public string Answer6 { get; set; }
}

这是我对自定义属性的尝试：

public class UniqueAnswersOnly: ValidationAttribute, IClientValidatable
    {

        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            //Get a list of all properties that are marked with [UniqueAnswersOnly]
            var props = validationContext.ObjectInstance.GetType().GetProperties().Where(
                prop => Attribute.IsDefined(prop, typeof(UniqueAnswersOnly)));

            var values = new HashSet<string>();

            //Read the values of all other properties
            foreach(var prop in props)
            {
                var pValue = (string)prop.GetValue(validationContext.ObjectInstance, null);
                if (prop.Name!=validationContext.MemberName && !values.Contains(pValue))
                {
                    values.Add(pValue);
                }
            }

            if (values.Contains(value))
            {
                return new ValidationResult("Duplicate answer", new[] { validationContext.MemberName });
            }
            return null;
        }

        public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
        {
            var rule = new ModelClientValidationRule()
            {
                ErrorMessage = metadata.DisplayName + " is required!",
                ValidationType = "duplicateanswers"
            };

            yield return rule;
        }
    }

我现在遇到的问题是，即使输入了重复的答案，验证也成功了。我仍然可以继续下一个对话框（如果输入重复项，我预计验证会失败）。我认为这是因为我的自定义属性没有被触发或命中，因为我添加了断点但没有命中。

在我的控制器中，我有 if(ModelState.IsValid) { //continue to next dialog} 并且模型状态 return 有效。

Answer 1

您可以像下面这样在您的模型中实现 IValidatableObject 接口，并使用 jQuery 来处理客户端的验证。

public class SecurityQuestions : IValidatableObject
{
    public int Question1Id { get; set; }

    public int Question2Id { get; set; }

    public int Question3Id { get; set; }

    public int Question4Id { get; set; }

    public int Question5Id { get; set; }

    public int Question6Id { get; set; }

    public string Answer1 { get; set; }

    public string Answer2 { get; set; }

    public string Answer3 { get; set; }

    public string Answer4 { get; set; }

    public string Answer5 { get; set; }

    public string Answer6 { get; set; }

    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        var securityAnswers = new List<string>();
        securityAnswers.Add(this.Answer1);
        securityAnswers.Add(this.Answer2);
        securityAnswers.Add(this.Answer3);
        securityAnswers.Add(this.Answer4);
        securityAnswers.Add(this.Answer5);
        securityAnswers.Add(this.Answer6);

        bool hasDuplicates = securityAnswers.GroupBy(x => x).Where(g => g.Count() > 1).Any();

        if (hasDuplicates)
        {
            yield return new ValidationResult(
                "There are duplicate Answers...");
        }
    }
}

Answer 2

您可以像这样创建自定义验证属性：

public class UniqueAnswersOnly : ValidationAttribute
{
    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        //Get a list of all properties that are marked with [UniqueAnswersOnly]
        var props = validationContext.ObjectInstance.GetType().GetProperties().Where(
            prop => Attribute.IsDefined(prop, typeof(UniqueAnswersOnly)));

        var values = new HashSet<string>();

        //Read the values of all other properties
        foreach(var prop in props)
        {
            var pValue = (string)prop.GetValue(validationContext.ObjectInstance);
            if (prop.Name!=validationContext.MemberName && !values.Contains(pValue))
            {
                values.Add(pValue);
            }
        }

        if (values.Contains(value))
        {
            return new ValidationResult("Duplicate answer", new[] { validationContext.MemberName });
        }
        return null;
    }
}

这是一个测试用例：

public class SecurityQuestions
{
    public int Question1Id { get; set; }
    public int Question2Id { get; set; }
    public int Question3Id { get; set; }
    public int Question4Id { get; set; }
    public int Question5Id { get; set; }
    public int Question6Id { get; set; }
    [UniqueAnswersOnly]
    public string Answer1 { get; set; }
    [UniqueAnswersOnly]
    public string Answer2 { get; set; }
    [UniqueAnswersOnly]
    public string Answer3 { get; set; }
    [UniqueAnswersOnly]
    public string Answer4 { get; set; }
    [UniqueAnswersOnly]
    public string Answer5 { get; set; }
    [UniqueAnswersOnly]
    public string Answer6 { get; set; }
}


class Program
{
    static void Main(string[] args)
    {
        var questions = new SecurityQuestions();
        questions.Answer1 = "Test";
        questions.Answer2 = "Test";
        questions.Answer3 = "Test3";
        questions.Answer4 = "Test4";
        questions.Answer5 = "Test5";
        questions.Answer6 = "Test6";

        var vc = new ValidationContext(questions, null, null);
        var results = new List<ValidationResult>();
        var validationResult = Validator.TryValidateObject(questions, vc, results, true);
    }
}

编辑：

我创建了一个默认 MVC 项目并添加了您当前的代码。该验证工作正常。

我将这个添加到家庭控制器：

    public ActionResult AskQuestions()
    {
        var questions = new SecurityQuestions();

        return View(questions);
    }

    [HttpPost]
    public ActionResult CheckQuestions(SecurityQuestions questions)
    {
        if (ModelState.IsValid)
        {
            return View();
        }            
        else
        {
            return HttpNotFound();
        }
    }

AskQuestions 视图如下所示：

@model WebApplicationValidation.Models.SecurityQuestions

@{
    ViewBag.Title = "AskQuestions";
}

<h2>AskQuestions</h2>


@using (Html.BeginForm("CheckQuestions", "Home",FormMethod.Post))
{
    @Html.AntiForgeryToken()

    <div class="form-horizontal">
        <h4>SecurityQuestions</h4>
        <hr />
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })
        <div class="form-group">
            @Html.LabelFor(model => model.Question1Id, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Question1Id, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Question1Id, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Question2Id, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Question2Id, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Question2Id, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Question3Id, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Question3Id, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Question3Id, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Question4Id, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Question4Id, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Question4Id, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Question5Id, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Question5Id, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Question5Id, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Question6Id, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Question6Id, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Question6Id, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Answer1, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Answer1, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Answer1, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Answer2, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Answer2, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Answer2, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Answer3, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Answer3, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Answer3, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Answer4, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Answer4, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Answer4, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Answer5, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Answer5, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Answer5, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.Answer6, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Answer6, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Answer6, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            <div class="col-md-offset-2 col-md-10">
                <input type="submit" value="Create" class="btn btn-default" />
            </div>
        </div>
    </div>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>

@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}

如果我运行应用程序，如果我输入两个相同的答案， ModelState.IsValid() 为假。在验证例程中设置断点表明它正在运行.

用于检查我的模型属性中的重复项的自定义验证属性未触发

Custom validation attribute to check for duplicates among my model properties is not firing

c#

asp.net-mvc

validation

asp.net-mvc-4

customvalidator