function checkForm() {
	if (document.getElementById('txtNaam').value == '') {
		alert(document.getElementById('err_namerequired').value);
		document.getElementById('txtNaam').focus();
		return false
	}
 	var tmpEmail = document.getElementById('txtEmail').value ;
	if (tmpEmail == '') {
		alert(document.getElementById('err_mailrequired').value);
		document.getElementById('txtEmail').focus();
		return false;
		}
	if (tmpEmail!= '') {
		if (!checkMail(tmpEmail)) {
			alert(document.getElementById('err_mailformat').value);
			document.getElementById('txtEmail').focus();
			return false;
			}
		}
	if (document.getElementById('txtRemarks').value == '') {
		alert(document.getElementById('err_remarksrequired').value);
		document.getElementById('txtRemarks').focus();
		return false
	}
	return true ;
}
function checkMail(tmpEmail){
	var x = tmpEmail ;
	var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	return filter.test(x);
	}