客户端列表的 MVC 自定义验证

我正在尝试编写一个在客户端运行的自定义验证器，用于验证所有复选框是否已被勾选.

I'm trying to write a custom validator that works on the client side that validates that all checkboxes have been ticked.

这是关于模型的声明:

[DeclarationsAccepted(ErrorMessage = "You must tick all declarations")]        
    public IList<DeclarationQuestion> DeclarationQuestions { get; set; }

这是属性:

public class DeclarationsAccepted : ValidationAttribute, IClientValidatable
{
    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {

        var questions = value as IList<DeclarationQuestion>;

        if (questions != null && questions.All(c => c.Answer))
        {
            return ValidationResult.Success;
        }
        return new ValidationResult("You must accepted all declarations to continue");
    }

    public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
    {
        var modelClientValidationRule = new ModelClientValidationRule
        {
            ValidationType = "declarationsaccepted",
            ErrorMessage = FormatErrorMessage(metadata.DisplayName)
        };            
        yield return modelClientValidationRule;
    }
}

到目前为止一切顺利，在服务器端工作.

So far so good, works server side.

对于客户端，我将其连接如下:

For the client I'm wiring this up as follows:

jQuery.validator.addMethod('declarationsaccepted', function (value, element, params) {

        //Implement logic here to check all boxes are ticked
        console.log(value);

        return false;
    }, '');


    jQuery.validator.unobtrusive.adapters.add('declarationsaccepted', {}, function (options) {
        options.rules['declarationsaccepted'] = true;
        options.messages['declarationsaccepted'] = options.message;
    });

我正在显示这样的复选框:

I'm displaying the checkboxes like this:

@{ var questionIndex = 0; }
        @foreach (var question in Model.DeclarationQuestions)
        {

                @Html.CheckBoxFor(model => Model.DeclarationQuestions[questionIndex].Answer, new { id = "DeclarationQuestions" + questionIndex})

            questionIndex++;
        }

然后使用此显示验证消息:

And then displaying the validation message using this:

@Html.ValidationMessageFor(c => c.DeclarationQuestions)

当我提交表单时，会显示消息，但仅在回发到服务器后才会显示.有没有办法让它在客户端工作?

When I submit the form the message is displayed but only after a post back to the server. Is there any way to get this to work on the client side?