I have bootstrap multiselect drop-down. I used following code to enable/disable element on page for specific drop-down value selection.
$("#drpList").change(function () {
var selection = $('#drpList option:selected');
var selected = [];
$(selection).each(function(index, brand){
selected.push([$(this).val()]);
alert(selected);
if (selected == 123) {
$("#txtComment").prop('disabled', true);
}
else {
$("#txtComment").prop('disabled', false);
}
});
});