function chkForm() {
	if (document.getElementById('txtName')) {
		if (document.getElementById('txtName').value == '') {
			alert(document.getElementById('err_namerequired').value);
			document.getElementById('txtName').focus();
			return false;
			}
		}
	if (document.getElementById('txtLastName')) {
		if (document.getElementById('txtLastName').value == '') {
			alert(document.getElementById('err_namerequired').value);
			document.getElementById('txtLastName').focus();
			return false;
			}
		}
	if (document.getElementById('txtEmail')) {
	 	var tmpEmail = document.getElementById('txtEmail').value ;
		if (tmpEmail == '') {
			alert(document.getElementById('err_emailrequired').value);
			document.getElementById('txtEmail').focus();
			return false;
			}
		if (tmpEmail!= '') {
			if (!checkMail(tmpEmail)) {
				alert(document.getElementById('err_emailformat').value);
				document.getElementById('txtEmail').focus();
				return false;
				}
			}
		}
	if (document.getElementById('txtName2')) {
		if (document.getElementById('txtName2').value == '') {
			alert(document.getElementById('err_friendnamerequired').value);
			document.getElementById('txtName2').focus();
			return false;
			}
		}
	if (document.getElementById('txtEmail2')) {		
	 	var tmpEmail = document.getElementById('txtEmail2').value ;
		if (tmpEmail == '') {
			alert(document.getElementById('err_friendemailrequired').value);
			document.getElementById('txtEmail2').focus();
			return false;
			}
		if (tmpEmail!= '') {
			if (!checkMail(tmpEmail)) {
				alert(document.getElementById('err_friendemailformat').value);
				document.getElementById('txtEmail2').focus();
				return false;
				}
			}
		}
	if (document.getElementById('txtRemarks')) {
		if (document.getElementById('txtRemarks').value == '') {
			alert(document.getElementById('err_inputrequired').value);
			document.getElementById('txtRemarks').focus();
			return false;
			}
		}
	return true ;
	}