Detecting input change in jQuery?

UPDATED for clarification and example

examples: http://jsfiddle.net/pxfunc/5kpeJ/

Method 1. input event

In modern browsers use the input event. This event will fire when the user is typing into a text field, pasting, undoing, basically anytime the value changed from one value to another.

In jQuery do that like this

$('#someInput').bind('input', function() { 
    $(this).val() // get the current value of the input field.
});

starting with jQuery 1.7, replace bind with on:

$('#someInput').on('input', function() { 
    $(this).val() // get the current value of the input field.
});

Method 2. keyup event

For older browsers use the keyup event (this will fire once a key on the keyboard has been released, this event can give a sort of false positive because when "w" is released the input value is changed and the keyup event fires, but also when the "shift" key is released the keyup event fires but no change has been made to the input.). Also this method doesn't fire if the user right-clicks and pastes from the context menu:

$('#someInput').keyup(function() {
    $(this).val() // get the current value of the input field.
});

Method 3. Timer (setInterval or setTimeout)

To get around the limitations of keyup you can set a timer to periodically check the value of the input to determine a change in value. You can use setInterval or setTimeout to do this timer check. See the marked answer on this SO question: jQuery textbox change event or see the fiddle for a working example using focus and blur events to start and stop the timer for a specific input field

If you've got HTML5:

• oninput (fires only when a change actually happens, but does so immediately)

Otherwise you need to check for all these events which might indicate a change to the input element's value:

• onchange
• onkeyup (not keydown or keypress as the input's value won't have the new keystroke in it yet)
• onpaste (when supported)

and maybe:

• onmouseup (I'm not sure about this one)

With HTML5 and without using jQuery, you can using the input event:

var input = document.querySelector('input');

input.addEventListener('input', function()
{
    console.log('input changed to: ', input.value);
});

This will fire each time the input's text changes.

Supported in IE9+ and other browsers.

Try it live in a jsFiddle here.