<!--
function ltrim(str)
{
	for (i=0; i<str.length; i++)
		if (str.charAt(i)!=" ") break;
	return str.substr(i);
}

function rtrim(str)
{
	for (i=str.length-1; i>-1; i--)
		if (str.charAt(i)!=" ") break;
	return str.substr(0, i+1);
}

function trim(str)
{
	return ltrim(rtrim(str));
}

function checkTime(s) {
	var i = s.indexOf(":");
	if (i<0) return false;
	var hh = s.substr(0, i);
	var mm = s.substr(i+1);

	if (!checkInt1(hh)) return false;
	if (!checkInt1(mm)) return false;

	h = hh.valueOf();
	m = mm.valueOf();

	if ((h<0) || (h>23)) return false;
	if ((m<0) || (m>59)) return false;

	return true;
}

function isValidDate(strDate)
{
  var retval = 0
  var aDDMMCCYY
  var dtest
  // Kiem tra dung format
  if (/^(\d\d?-\d\d?-\d{4})|(\d\d?\/\d\d?\/\d{4})|(\d{8})$/.test(strDate))
  {
    if (/\//.test(strDate))
    {
      aDDMMCCYY = strDate.split("/");
    }
    else
    if (/-/.test(strDate))
    {
      aDDMMCCYY = strDate.split("-");
    }
    else
    {
      aDDMMCCYY = Array(strDate.substr(0,2), strDate.substr(2,2), strDate.substr(4,4))
    }    
	dtest = new Date(aDDMMCCYY[1] + "/" + aDDMMCCYY[0] + "/" + aDDMMCCYY[2]);      
    if (dtest.getDate() != aDDMMCCYY[0] || dtest.getMonth() +1 != aDDMMCCYY[1] || dtest.getFullYear() != aDDMMCCYY[2])
    {
      retval = 2
    }
  }
  else
  {
	retval = 1
  }
  return retval
}

function checkDate(s) {
	var i1 = s.indexOf("/");
	if (i1<0) return false;
	var i2 = s.indexOf("/",i1+1);
	if (i2<0) return false;
	var dd = s.substr(0, i1);
	var mm = s.substr(i1+1, i2-(i1+1));
	var yy = s.substr(i2+1);

	if (!checkInt(dd)) return false;
	if (!checkInt(mm)) return false;
	if (!checkInt(yy)) return false;

	d = dd.valueOf();
	m = mm.valueOf();
	y = yy.valueOf();

	if ((m<1) || (m>12)) return false;
	if (y<1) return false;
	var leapyear=( (y % 4)==0 );
	var maxday=0;

	maxday=31;
	if ((m==4) || (m==6) || (m==9) || (m==11))
		maxday=30;
	if (m==2)
		maxday=(leapyear)?29:28;

	if ((dd.valueOf()<1) || (dd.valueOf()>maxday)) return false;
	return true;
}
function formatNgay(strNgay)
{
	var s="";
	var arr;
	n=strNgay.indexOf("/")
	if (n!=-1)
	{
		arr=strNgay.split("/")
		s=arr[1] + "/" + arr[0] + "/" + arr[2]
	}
	else
	{
		n=strNgay.indexOf("-")
		if (n!=-1)
		{
			arr=strNgay.split("-")
			s=arr[1] + "-" + arr[0] + "-" + arr[2]
		}	
	}
	return (s);
}
function dateUTC(s) {
	var i1 = s.indexOf("/");
	var i2 = s.indexOf("/",i1+1);
	var dd = s.substr(0, i1);
	var mm = s.substr(i1+1, i2-(i1+1));
	var yy = s.substr(i2+1);
	return Date.UTC(yy, mm-1, dd);
}

function lessDate(s1, s2) {
	return (dateUTC(s1) < dateUTC(s2));
}
//return true neu d1>d2
function SoSanhNgay(d1,d2){
	dtest1 = new Date(formatNgay(d1));
	dtest2 = new Date(formatNgay(d2));
		y1=dtest1.getFullYear()
		y2=dtest2.getFullYear()
		m1=dtest1.getMonth()
		m2=dtest2.getMonth()
		d1=dtest1.getDate()
		d2=dtest2.getDate()
		if (y1 < y2)
			return false;
		if (y1 == y2)
		{
		if (m1 < m2)
			return false;
		if (m1 == m2)
			if (d1 < d2)
				return false;
		}
	return true;
}
function checkInt(checkStr) {
	if (checkStr.length < 1) return false;
	var checkOK = "0123456789";
	for (i=0; i<checkStr.length; i++) {
		ch = checkStr.charAt(i);
		if (checkOK.indexOf(ch) < 0)
			return false;
	}
	if (checkStr.valueOf()<1) return false;
	return true;
}

function checkInt1(checkStr) {
	if (checkStr.length < 1) return false;
	var checkOK = "0123456789";
	for (i=0; i<checkStr.length; i++) {
		ch = checkStr.charAt(i);
		if (checkOK.indexOf(ch) < 0)
			return false;
	}
	return true;
}

function checkRange(checkStr, minR, maxR) {
	if (!checkInt(checkStr)) return false;
	var v = checkStr.valueOf();
	return ((v>=minR) && (v<=maxR));
}

function checkDouble(checkStr) {
	if (checkStr.length < 1) return false;
	var checkOK = "0123456789.";
	for (i=0; i<checkStr.length; i++) {
		ch = checkStr.charAt(i);
		if (checkOK.indexOf(ch) < 0)
			return false;
	}
	if (checkStr.indexOf(".")!=checkStr.lastIndexOf("."))
		return false;
	return true;
}

function validDouble(st, n)
{
// implement later
// n: so chu so trong phan thap phan
	var i = st.lastIndexOf(".");
	if (i>-1) return ( (st.substr(i+1)).length <= n );
	return true;
}

function checkdata()
{
	alert("ok");
}

function check_data(obj,k,st)
  {
	var str = obj.value;
	if(k=='d'){
		if (str!=""){
			if (isValidDate(str)!=0){
				if (st=="")	alert("Vui lòng nhập ngày dạng: dd/mm/yyyy.");
				else	alert(st);
				obj.value="";
				obj.focus();
				return false;
				}
			}
		}
	if(k=='n'){
	 	if ( trim(str) !="") {
			if (!checkInt(str)) {
				if (st=="")	alert("Vui lòng nhập bằng số.");
				else	alert(st);
				obj.value="";
				obj.focus();
				return false;
				}
  			}
		}
	if(k==""){
		if (trim(str) == "") {
 			if (st=="")	alert("Vui long nhap them thong tin. Cam on!");
 			else	alert(st); 
			//obj.focus();
			return false;
			}
		}
	return true;	
  }
function Check_Email(strEmail)
{

	if(strEmail != "")
	{
		var len = strEmail.length;
		var ch = strEmail.charAt(len-1);
		if (strEmail.indexOf("@")<1)
			return false;
		if (strEmail.indexOf("@")!=strEmail.lastIndexOf("@"))
			return false;
		if(ch=="@")
			return false;
		if (strEmail.indexOf(".")<1)
			return false;
	}
	return true;
}	
//-- show current date from local user in Vietnamese lang. - utf-8 codepage
function showDateVN() {
// variables declaration
var dt=new Date();
var strMonth = new Array("01","02","03","04","05","06","07","08","09","10","11","12");
var strDay = new Array("Sunday","Monday","Tuesday","Wednesday","Thurday","Friday","Saturday");
var date=strDay[dt.getDay()] + ", ";
var years= dt.getYear();
if (years<1900) years+= 1900;
return (date += "Date "+dt.getDate()+" month  "+strMonth[dt.getMonth()] + " year "+years);
}
//-->