jquery :contains() case insensitive selector

jquery-contaninsi.js

$.extend($.expr[':'], {	//definizione di :conaints() case insesitive
	'containsi': function(elem, i, match, array)
	{
		return (elem.textContent || elem.innerText || '').toLowerCase()
				.indexOf((match[3] || "").toLowerCase()) >= 0;
	}
});

//example
$("a:containsi('text')");