Answers for "Select 2"

get value select 2

//get selected value
$('#mySelect2').find(':selected').val();

Select 2

<link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/select2.min.css" rel="stylesheet" />
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/select2.min.js"></script>

select2 documentation

$('.js-example-basic-single').select2({
  placeholder: 'Select an option'
});

select 2 select a value

SELECT2 V4 :
============
For select2 v4 you can append directly an option/s as follow:

<select id="myMultipleSelect2" multiple="" name="myMultipleSelect2[]">
    <option value="TheID" selected="selected">The text</option>                                                                   
</select>

Or with JQuery:
---------------

var $newOption = $("<option selected='selected'></option>").val("TheID")
					.text("The text")
 
$("#myMultipleSelect2").append($newOption).trigger('change');

other example :
---------------

$("#myMultipleSelect2").val(5).trigger('change');