https://cedar.carmel.ac.uk/Static/Lib/jQuery/plugins/jquery.capslock.js

1/*
2 * Capslock 0.2 - jQuery plugin to detect if a user's caps lock is on or not.
3 * 
4 * Provides events, "caps_lock_on" and "caps_lock_off", that custom functions can be bound to.
5 * The capslock function can be called on a specific element, a set of elements, or globally:
6 * 		$("#my_textarea").capslock(options);	// One textarea
7 * 		$("textarea").capslock(options);		// All textareas
8 * 		$().capslock(options);					// Globally
9 *
10 * Copyright (c) 2009 Arthur McLean
11 *
12 * Dual licensed under the MIT and GPL licenses:
13 *   http://www.opensource.org/licenses/mit-license.php
14 *   http://www.gnu.org/licenses/gpl.html
15 *
16 */
17
18; // Just in case the previously included plug-in failed to close with a semi-colon.
19(function($) {
20	
21	$.fn.capslock = function(options) {
22		
23		if (options) $.extend($.fn.capslock.defaults, options);
24		
25		this.each(function() {
26			$(this).bind("caps_lock_on", $.fn.capslock.defaults.caps_lock_on);
27			$(this).bind("caps_lock_off", $.fn.capslock.defaults.caps_lock_off);
28			
29			$(this).keypress(function(e){
30				check_caps_lock(e);
31			});
32		});
33		
34		return this;
35	};
36	
37
38	
39	// The actual check:
40	function check_caps_lock(e)
41	{
42		var ascii_code	= e.which;
43		var shift_key	= e.shiftKey;
44		if( (65 <= ascii_code) && (ascii_code <= 90) && !shift_key)
45		{
46			$(e.target).trigger("caps_lock_on");
47		}
48		else
49		{
50			$(e.target).trigger("caps_lock_off");
51		}
52		
53	}
54	
55	// Public definition of defaults for easy overriding:
56	$.fn.capslock.defaults = {
57		caps_lock_on:	function() {},
58		caps_lock_off:	function() {}
59	};
60	
61})(jQuery);
62