Auto populate field base on what was entered in another field simultaneously

Question

I was trying to figure out how to auto-populate the input value base on what was entered in another input field using javascript. Here\'s my code:

Answer 1

I made a general example :

HTML

javascript

$(".first").on('keyup',function(){
    $(".second").val($(this).val());
});

http://jsfiddle.net/fmdwv/1/

For your purpose :

$("#address").on('change', function(){
  $("#shipping-address-1").val($(this).val());
});