ID는 문서에서 고유해야 합니다. −
var option_avail = $('input[name=option_avail]:checked', '#controls').val() <label class="btn btn-primary active"> <input type="radio" class="form-control" name="option_avail" value="Option_one" checked /> firstoption </label> <label class="btn btn-primary "> <input type="radio" class="form-control" name="option_avail" value="Option_two" /> secondoption </label> <label class="btn btn-primary "> <input type="radio" class="form-control" name="option_avail" value="Option_three" /> thirdoption </label>