How to detect a textbox's content has changed

Question

I want to detect whenever a textbox\'s content has changed. I can use the keyup method, but that will also detect keystrokes which do not generate letters, like the arrow ke

Answer 1

There's a complete working example here.

$(document).ready(function() {
$('.calc').on('input', function() {
var t1 = document.getElementById('txt1');
var t2 = document.getElementById('txt2');
var tot=0;
if (parseInt(t1.value))
tot += parseInt(t1.value);
if (parseInt(t2.value))
tot += parseInt(t2.value);
document.getElementById('txt3').value = tot;
});
});