Answers for "on change jquery selected value"

select onchange get value jquery

$('#the_id_select').on('change', function() {
  alert( this.value );
});

//or

$("#the_id_select").change(function(){
   alert( this.value );
});

.on change get value

$('select').on('change', function() {
  alert( this.value );
});

jQuery change select value

$("#mySelectElementID").val("my_new_value"); //change selected option/value with jQuery

jquery detect textarea change

$('#myTextAreaID').on('input propertychange paste', function() {
    //my Textarea content has changed
});