Validate a Hidden Field - asp.net-mvc-3

Question

I'm using MVC3 with unobtrusive validation. I have a field that the user is expected to fill with some data and then press a "search" button. If search has never been pressed or the user has changed the input field after pressing search, the form should not be possible to submit.
I've added a hidden field that is set to true by the click() event of the button and emptied by the keyup() event of the input box. Now I would like to add a validation rule that requires the hidden field to be true to allow submit.
Preferably I would like to use unobtrusive validation, but if that doesn't work it is ok with something that requires some javascript, as long as it doesn't spoil the unobtrusive validation for the rest of the form.
The following code snippet does exactly what I want, until I add type="hidden".
<input class="required" id="client-searched" data-val="true"
name="ClientSearched" data-val-required="Press search!"/>
<span class="field-validation-valid" data-valmsg-replace="true"
data-valmsg-for="ClientSearched"/>

Answer 1

try
var validator = $("#myFormId").data('validator');
validator.settings.ignore = "";
Here is an informative blog post
EDIT
#RAM suggested a better solution please FOLLOW

Answer 2

I had a similar problem, and I used this code to change defaults, in MVC 4:
#Scripts.Render("~/bundles/jqueryval")
<script type="text/javascript">
$.validator.setDefaults({
ignore: ""
})
</script>
Source:
JQuery validate

Answer 3

In some cases you want just ignore validation on one or several
hidden fields (not all hidden field) in client side and also you want validate them and other hidden fields in server side.
In these cases you have validation attributes for all hidden fields in your ViewModel and they will be used to validate the form when you post it (server side).
Now you need a trick to just validate some of the hidden fields in client side (not all of them). In these cases i recommend you to use my mechanism!
Set data-force-val as true in the target hidden input tags. It's our custom attribute that we use to detect target hidden inputs witch we want validate them in client side.
// This hidden input will validate both server side & client side
<input type="hidden" value="" name="Id" id="Id"
data-val-required="The Id field is required."
data-val="true"
data-force-val="true">
// This hidden input will validate both server side & client side
<input type="hidden" value="" name="Email" id="Email"
data-val-required="The Email field is required."
data-val="true"
data-force-val="true">
// This hidden input just will validate server side
<input type="hidden" value="" name="Name" id="Name"
data-val-required="The Neme field is required."
data-val="true">
Also you can set data_force-val for your hidden inputs by jQuery:
$("#Id").attr("data-force-val", true); // We want validate Id in client side
$("#Email").attr("data-force-val", true); // We want validate Email in client side
$("#Name").attr("data-force-val", false); // We wont validate Name in client side (This line is not necessary, event we can remove it)
Now, active data-force-val="true" functionality by some simple codes like these:
var validator = $("#TheFormId").data('validator');
validator.settings.ignore = ":hidden:not([data-force-val='true'])";
Note: validator.settings.ignore default value is :hidden