Number.prototype.formatMoney = function(c, d, t){
    var n = this, c = isNaN(c = Math.abs(c)) ? 2 : c, d = d == undefined ? "," : d, t = t == undefined ? "." : t, s = n < 0 ? "-" : "",
    i = parseInt(n = Math.abs(+n || 0).toFixed(c)) + "", j = (j = i.length) > 3 ? j % 3 : 0;
    return s + (j ? i.substr(0, j) + t : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t)
    + (c ? d + Math.abs(n - i).toFixed(c).slice(2) : "");
};

$(function() {
	$("#afmeting")
		.bind("change", function() {
			$("#prijs").html(parseFloat(aryAfmeting[this.selectedIndex] * $('#aantal').attr('value')).formatMoney(2, ',', '.'));
		});
	$("#aantal")
		.bind("keyup", function() {
			$("#prijs").html((aryAfmeting[$("#afmeting").attr('selectedIndex')] * this.value).formatMoney(2, ',', '.'))
		});

});