Multiple fields validation using Remote Validation

Question

I have the following model:

public class Customer
{
    public string FirstName {get;set;}

    public string LastName {get; set;}

    [Remote("CardExisting", "Validation", AdditionalFields="FirstName,LastName")
    public string CardNumber {get; set;}
}

CardExisting action will check that there is an existing record for the combination of cardNumber for the firstName and LastName.

What if user will first enter the card number and then his name, I cant validate him, so when he returns and input his name I need to remote validate again, how can I do that when focus was already lost from cardnumber property?

Answer 1

Expanding on Jaluka's answer, I wrote this helper method that finds each remotely validating element that has "additional fields," and then causes validation on said element to fire each time one of those fields changes.

// I hate naming things
function initializeRemotelyValidatingElementsWithAdditionalFields($form) {
    var remotelyValidatingElements = $form.find("[data-val-remote]");

    $.each(remotelyValidatingElements, function (i, element) {
        var $element = $(element);

        var additionalFields = $element.attr("data-val-remote-additionalfields");

        if (additionalFields.length == 0) return;

        var rawFieldNames = additionalFields.split(",");

        var fieldNames = $.map(rawFieldNames, function (fieldName) { return fieldName.replace("*.", ""); });

        $.each(fieldNames, function (i, fieldName) {
            $form.find("#" + fieldName).change(function () {
                // force re-validation to occur
                $element.removeData("previousValue");
                $element.valid();
            });
        });
    });
}

Call the function like so:

$(document).ready(function() {
    initializeRemotelyValidatingElementsWithAdditionalFields($("#myFormId"));
});