var emailRegExp  = /([_a-z0-9A-Z][^à-ú]+)(\.[_a-z0-9A-Z][^à-ú]+)*@([a-z0-9A-Z-][^à-ú]+)(\.[_a-z0-9A-Z][^à-ú]+)*[^\.]$/;
var numberRegExp = /^\s*\d+\s*$/;
var dateRegExp1  = /(0[1-9]|[12][0-9]|3[01])[/](0[1-9]|1[012])[/](19|20)\d\d/ //dd/mm/yyyy

function isEmpty(elementId, errorMessage){	
	if(document.getElementById(elementId).value == "") return alertAndFocus(elementId, errorMessage);
	return false;
}

function isPhone(elementId, errorMessage, must){
var value = document.getElementById(elementId).value;

	if(!must && value == "") return true;
	if(value.length < 7) return !alertAndFocus(elementId, errorMessage);
	if(!isNumber(value)) return !alertAndFocus(elementId, errorMessage);
	return true;
}

function isEmail(elementId, errorMessage, must){
var reg	  = new RegExp(emailRegExp);
var value = document.getElementById(elementId).value;

	if(!must && value == "") return true;
	if(!reg.test(value)) return !alertAndFocus(elementId, errorMessage);
	return true;
}

function isNumber(value){
	return new RegExp(numberRegExp).test(value);
}

function isDate1(elementId, errorMessage, must){
var reg	  = new RegExp(dateRegExp1);
var value = document.getElementById(elementId).value;

	if(!must && value == "") return true;
	if(!reg.test(value)) return !alertAndFocus(elementId, errorMessage);
	return true;
}

function alertAndFocus(elementId, errorMessage){
	alert(errorMessage);
	document.getElementById(elementId).focus();
	return true;
}