Answers for "select2 multiselect repeat values selected"

select2 multi select get selected value

alert("Selected value is: "+$(".leaderMultiSelctdropdown").select2("val"));

alternatively, if you used a regular selectbox as base, you should be able to
use the normal jquery call, too:

alert("Selected value is: "+$(".leaderMultiSelctdropdown").val());

select2 multiple selected values

in_array($value, $array)