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[JS] Check select2 jquery plugin loaded or notRead How to async defer CSS JS perfectly


if (jQuery.fn.select2) { //jquery select2 loaded or not false or not undefined => return array
  jQuery.fn.select2.defaults.set( "theme", "bootstrap" ); //then select themes
}

Example: How to change select2 jQuery plugin using jQuery.val()


  $('#mySelect2').val('US'); // Change the value or make some change to the internal state
if (jQuery.fn.select2) {
  $('#mySelect2').trigger('change.select2'); // Notify only Select2 of changes
}