function isValidEmail(str) {
	if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(str)) return (true);
	return (false);
}

function isValidString(str) {
	return (str.length > 0);
}

function isValidNumber(str) {
	if (isNaN(str)) return false;
	if (str == "") return false;
	if (str < 0) return false;
	return true;
}

function isValidRadio(myRadio) {
	myOption = -1;
	for (i=myRadio.length-1; i > -1; i--) {
		if (myRadio[i].checked) {
			myOption = i;
		}
	}

	return (myOption != -1);
}

function isLegalDrinkingAge(day,month,year) {
	today = new Date();
	thisYear = today.getYear();
	thisMonth = today.getMonth();
	thisDay = today.getDay();

	var yearsold = thisYear - year, monthsold = 0, daysold = 0, string = '';

	if (thisMonth >= month) monthsold = thisMonth - month;
		else { yearsold--; monthsold = thisMonth + 12 - month; }

	if (thisDay >= day)daysold = thisDay - day;
		else {
			if (monthsold > 0) monthsold--;
				else { yearsold--; monthsold+=11; }
		daysold = thisDay + 31 - day;
	}

	if (yearsold >= 18) return true;
	return false;
}