jquery.maxlength.js

(function($) {
	$.fn.maxlength = function(options) {
		var settings = $.extend({
			maxWords:		60,
			badClass:		false, // apply this class to an invalid element
			statusIdSuffix:	        '_wc', // hold the words remaining information (elementId_wc)
			errorMsg: 		'To many words have been entered in this field.',
		}, options);
		
		return this.each(function() {
			var el = $(this);
			if (!el.is('textarea'))
				return false;
			
			el.keypress(function(e) {
				var wc = el.val().split(/[\s\.\?]+/).length;
				if (settings.statusIdSuffix) {
					statusEl = $('#' + this.id + settings.statusIdSuffix);
					if (statusEl.length) 
						statusEl.text(wc + '/' + settings.maxWords);
				}
				
				if (wc >= settings.maxWords) {
					$(el[0].form).find('input[type=submit]').attr('disabled', 'disabled');
					statusEl.text(statusEl.text() + ' ' + settings.errorMsg);
					if (settings.badClass)
						el.addClass(settings.badClass);
				} else {
					$(el[0].form).find('input[type=submit]').attr('disabled', '');
					el.removeClass(settings.badClass);
				}
			});
		});
	};
})(jQuery);