How can I check which of the two radio button is checked in javascript/jquery? [duplicate]

Question

How can I check which of the two radio button is checked in javascript/jquery in order to get the value of the input considering the fact that, in the HTML, both of them are by default unchecked (no checked attribute is added)

<input type="radio" name="AS88" value="true" required>
<input type="radio" name="AS88" value="false">

The following code does not work:

var elements = document.getElementsByName("AS88");
for (var i=0, len=elements.length; i<len; ++i) {
    if (elements[i].checked) {
        alert(elements[i].value)
    } 
};

EDIT:

Solutions with :checked in jquery such as:

$('input[name="AS88"]:checked').val();

always return undefined

Answer 1

use attribute selector along with :checked selector and .val() to get the value of the checked input element with name AS88

$('input[name="AS88"]:checked').val()

Demo: Fiddle