Фетка набор проверяется jQuery
.prop('checked', true);
Helpful Herring
.prop('checked', true);
//selected checkbox alert boolen value return
$('#test').click(function() {
alert("Checkbox state (method 1) = " + $('#test').prop('checked'));
alert("Checkbox state (method 2) = " + $('#test').is(':checked'));
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
Check me: <input id="test" type="checkbox" />
//@sujaY