// Check that an email address is valid based on RFC 821 (?)
function isValidEmail(address) {
	if (address.indexOf('@') < 3) return false;
	var period = address.indexOf('.');
	if (period == -1) return false;
	var name = address.substring(0, address.indexOf('@'));
	var domain = address.substring(address.indexOf('@') + 1);
	if (name.indexOf('(') != -1 || name.indexOf(')') != -1 || name.indexOf('<') != -1 || name.indexOf('>') != -1 || name.indexOf(',') != -1 || name.indexOf(';') != -1 || name.indexOf(':') != -1 || name.indexOf('\\') != -1 || name.indexOf('"') != -1 || name.indexOf('[') != -1 || name.indexOf(']') != -1 || name.indexOf(' ') != -1) return false;
	if (domain.indexOf('(') != -1 || domain.indexOf(')') != -1 || domain.indexOf('<') != -1 || domain.indexOf('>') != -1 || domain.indexOf(',') != -1 || domain.indexOf(';') != -1 || domain.indexOf(':') != -1 || domain.indexOf('\\') != -1 || domain.indexOf('"') != -1 || domain.indexOf('[') != -1 || domain.indexOf(']') != -1 || domain.indexOf(' ') != -1) return false;
	return true;
}


function validform() {
	var f = document.mainform;
	if (f.name.value == '') {
		alert('Please enter your name');
		return false;
	} else if (!(isValidEmail(f.email.value))) {
		alert('Please enter your email address');
		return false;
	} else if (f.address.value == '') {
		alert('Please enter your address');
		return false;
	} else if (f.city.value == '') {
		alert('Please enter your city');
		return false;
	} else if (f.zip.value == '') {
		alert('Please enter your zip code');
		return false;
        } else if (f.yearofbirth.value == '') {
		alert('Please enter the year you were born in');
		return false;
//	} else if (f..value == '') {
	}

/*********************************************************************************************************************
	Add the name of the new field like the ones above. copy the line beginning with '//' and then remove the '//'
*********************************************************************************************************************/

	return true;
}