function CheckEmail(obj){
    var re = /^([A-Za-z0-9\_\-]+\.)*[A-Za-z0-9\_\-]+@[A-Za-z0-9\_\-]+(\.[A-Za-z0-9\_\-]+)+$/;
    var sEMail = obj.value;
    if (sEMail.search(re) == -1){
			return (false);
		}
	else{
		return (true);
    }
}
function CheckForm () { 
	var f = document.frmContact;
	if(f.ten.value=="") {
		alert("Please enter your name");
		f.ten.focus();
		return false;
	}
	if(f.email.value=="") {
		alert("Please enter your Email");
		f.email.focus();
		return false;
	}
	if(!CheckEmail(f.email)) {
		alert("Email incorrect");
		f.email.focus();
		f.email.select();
		return false;
	}
	if(f.tieude.value=="") {
		alert("Please enter subject");
		f.tieude.focus();
		return false;
	}
	
	if(f.noidung.value=="") {
		alert("Please enter contact message");
		f.noidung.focus();
		return false;
	}
	
	return true;
	
}