var EMAIL_REGEX  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
var NUMBER_REGEX = /^[+-]?([0-9]*\.?[0-9]+|[0-9]+\.?[0-9]*)([eE][+-]?[0-9]+)?$/;

function validEmailAddress(emailAddress) {
	var email = emailAddress.toString();
	if (email.length > 0) {
		return EMAIL_REGEX.test(emailAddress);
	}
	return false;
};

function validNotEmpty(string) {
	return string.toString().length > 0;
};

function validPasswordConfirm(newPassword, confirmPassword) {
	if (newPassword == confirmPassword) {
		return true;
	}
	return false;
};

function validCheckbox(checkboxId) {
	return (document.getElementById(checkboxId).checked == true);
};

function validCheckboxByElement(elem) {
	return elem.checked == true;
};