Not able to get it work clientside validation for IEnumerable in MVC3

Question

I simply list the checkboxes to select languages whose a developer get talented.I like to put a validation that at least one language must be selected.

Server side validation works with no fail.However i have not been able to get it work at client side.Even "GetClientValidationRules" method never called.Thats the point i curiosly wonder.

Is IEnumerable not supported for clientside validation ?What is the ways of doing this?

ps:I neednt to put the js validation codes because i think it will be ok once GetClientValidationRules is called

View: (Simplified for brevity)

public class DeveloperViewModel
{        
    [DeveloperLanguageSelectOneValidation(ErrorMessage="Please check at least one lang")]
    public IEnumerable<SelectListItem> LanguagesModel { get; set; }

}

Validation:

public class DeveloperLanguageSelectOneValidationAttribute : ValidationAttribute ,IClientValidatable
{
    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        IEnumerable<SelectListItem> items = (IEnumerable<SelectListItem>)value;
        foreach (var item in items)
            if (item.Selected)
                return ValidationResult.Success;
        return new ValidationResult(FormatErrorMessage(validationContext.DisplayName));
    }

    public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
    {
        var rule = new ModelClientValidationRule() 
        {
            ErrorMessage = FormatErrorMessage(metadata.GetDisplayName()),
            ValidationType = "developerlanguageselectone"                        
        };

        return new[] { rule };
    }
}

SelectListItem View:

@model SelectListItem
<li>
    @Html.HiddenFor(a => a.Value)
    @Html.CheckBoxFor(a => a.Selected)
    @Html.DisplayFor(a => a.Text)
</li>

Developer View :

 <ul>
        @Html.EditorFor(a => a.LanguagesModel)</ul>
    @Html.ValidationMessageFor(a => a.LanguagesModel)

score 0 · Answer 1 · edited May 23 '17 at 10:24

How about using jquery?

$.validator.addMethod('require-one', function(value) {
    return $('.require-one:checked').size() > 0;
}, 'Please check at least one box.');

var checkboxes = $('.require-one');
var checkbox_names = $.map(checkboxes, function(e, i) {
    return $(e).attr("name")
}).join(" ");

$("#itemForm").validate({
    groups: {
        checks: checkbox_names
    },
    errorPlacement: function(error, element) {
        if (element.attr("type") == "checkbox") error.insertAfter(checkboxes.last());
        else error.insertAfter(element);
    }
});

Your form:

<form name="itemForm" id="itemForm" method="post">

<label for="checkbox1">checkbox1</label>
<input checked="checked" data-val="true" data-val-required="The checkbox1 field is required." id="checkbox1" name="checkbox1" type="checkbox" value="true" class="require-one" />
<input name="checkbox1" type="hidden" value="false" /><br />

<label for="checkbox2">checkbox2</label>
<input checked="checked" data-val="true" data-val-required="The checkbox2 field is required." id="checkbox2" name="checkbox2" type="checkbox" value="true" class="require-one" />
<input name="checkbox2" type="hidden" value="false" /><br />

<label for="checkbox3">checkbox3</label>
<input checked="checked" data-val="true" data-val-required="The checkbox3 field is required." id="checkbox3" name="checkbox3" type="checkbox" value="true" class="require-one" />
<input name="checkbox3" type="hidden" value="false" /><br />

<input type="submit" />
</form>

From: https://stackoverflow.com/a/11512622/1026898

Thanks for the reply.Is there any chance to work this validation in unobtrusive way ? — sercan, Dec 02 '12 at 21:59

Not able to get it work clientside validation for IEnumerable in MVC3

1 Answers1