Answers for "how to get only checked checkbox value in jquery"

jquery checkbox checked value

if ($('#check_id').is(":checked"))
{
  // it is checked
}

jquery get value checkbox checked

console.log($('input[name="locationthemes"]:checked').serialize());

//or

$('input[name="locationthemes"]:checked').each(function() {
   console.log(this.value);
});