If the checkbox is checked, then I only need to get the value as 1; otherwise, I need to get it as 0. How do I do this using jQuery?
$("#ans").val() will always give me one right in this case:
<input type="checkbox" id="ans" value="1" />
Use .is(':checked') to determine whether or not it's checked, and then set your value accordingly.
$("#ans").attr('checked')
will tell you if it's checked. You can also use a second parameter true/false to check/uncheck the checkbox.
$("#ans").attr('checked', true);
Per comment, use prop instead of attr when available. E.g:
$("#ans").prop('checked')
Just use $(selector).is(':checked')
It returns a boolean value.