function checkemail(field, fieldname) {
	if (checkfield(field, fieldname)) {
		// Check for valid email address
		var filter=/^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+.[a-zA-Z]{2,4}$/;
		var fld = $('#' + field);
		if (!filter.test(fld.val())) {
			$('#errors').append('Het ingevoerde email adres is niet geldig.<br />');
			fld.addClass('error');
			return false;
		}
		fld.removeClass('error');
		return true;
	}
	return false;
}

function checkfield(field, fieldname) {
	var fld = $('#' + field);
	if (fld.val().length == 0) {
		jQuery('#errors').append('Veld "' + fieldname + '" is niet ingevuld.<br />');
		fld.addClass('error');
		return false;
	}
	fld.removeClass('error');
	return true;
}

function validate(formname)
{
	$('#errors').empty();

	var valid = checkfield('naam', 'Naam');
	valid = checkfield('adres', 'Adres') && valid;
	valid = checkfield('telefoonnummer', 'Telefoonnummer') && valid;
	valid = checkemail('email', 'Email adres') && valid;
	valid = checkfield('hond', 'Naam hond') && valid;
	valid = checkfield('ras', 'Ras') && valid;
	valid = checkfield('geboortedatum', 'Geboortedatum hond') && valid;
	if (!valid) {
		$('#errors').slideDown();
	} else {
		document.forms[formname].submit();
	}
}