SO fiddle

Test Fiddle mainly for SO Questions

by Nick Craver

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8/themes/dot-luv/jquery-ui.css">
<input id="my_field" type="text" />

JavaScript

$(document).ready(function(){
  $("#my_field").keydown(function (e) {
     alert (String.fromCharCode(e.which));
  });
});