var id_arr = new Array();
var str_name_arr = new Array();
var EmptyField = ' is not filled';
var WrongField = ' is not valid';
var error_str = '';

function text (str) { return /[A-ÿ0-9_;:'!~?=+<|>]/.test(str); }

function numeric (str) { return /^[0-9-\+\(\)\s]+z/.test(str + "z"); }

function mail (str) { return /^[a-z0-9_\.]+@[a-z0-9_\.]+.[a-z]{2,3}$/.test(str); }

function chdate (str) { return /(19|20)\d\d[- /.](0[1-9]|1[012])[- /.](0[1-9]|[12][0-9]|3[01])/.test(str); }

function file (str) { return /\.(jpg|png|jpeg|gif)$/i.test(str); }

function checkMail(id, str_name) 
{
	var elem = document.getElementById(id).value;
	if (elem.length == 0) return str_name+EmptyField ;
	else 
	if (!mail(elem)) return str_name+WrongField ;
	return error_str;
}

function checkNumeric(id, str_name) 
{
	elem = document.getElementById(id).value;
	if (elem.length == 0) return str_name+EmptyField;
	else if (!numeric(elem)) return str_name+WrongField;
	return error_str;
}

function checkText(id_arr, str_name_arr) 
{
	var i=0;
	for (i=0; i <= id_arr.length-1; i++)
	{
		elem = document.getElementById(id_arr[i]).value;
		if (elem.length == 0) { error_str += str_name_arr[i]+EmptyField+"<br />"; }
		else if (!text(elem)) { error_str += str_name_arr[i]+WrongField+"<br />"; }
	} 
	return error_str;
}

function checkDate(id, str_name) 
{
	elem = document.getElementById(id).value;
	if (elem.length == 0) return str_name+EmptyField;
	else if (!chdate(elem)) return str_name+WrongField;
	return error_str;
}

function checkFile(id, str_name) 
{
	elem = document.getElementById(id).value;
	if (elem.length == 0) return str_name+EmptyField;
	else if (!file(elem)) return str_name+WrongField;
	return error_str;
}