Options with display:none not hidden in IE

Question

I have multiple options in a select. I have sorted the options and disabled and hidden the duplicate options with jquery. The code works well in chrome and firefox but in IE

Answer 1

sort by disabled options. 

$("#addselect option").each(function (i, val) {
                if ($(this)[i].disabled) {
                    moveDown("selectId");
                }
                else {
                    moveUp("selectId");
                }
 }

   function moveUp(selectId) {
            var selectList = document.getElementById(selectId);
            var selectOptions = selectList.getElementsByTagName('option');
            for (var i = 1; i < selectOptions.length; i++) {
                var opt = selectOptions[i];
                if (!opt.disabled) {
                    selectList.removeChild(opt);
                    selectList.insertBefore(opt, selectOptions[i - 1]);
                }
            }
        }

        function moveDown(selectId) {
            var selectList = document.getElementById(selectId);
            var selectOptions = selectList.getElementsByTagName('option');
            for (var i = selectOptions.length - 2; i >= 0; i--) {
                var opt = selectOptions[i];
                if (opt.disabled) {
                    var nextOpt = selectOptions[i + 1];
                    opt = selectList.removeChild(opt);
                    nextOpt = selectList.replaceChild(opt, nextOpt);
                    selectList.insertBefore(nextOpt, opt);
                }
            }
        }