function isEmpty(nodeId){
	var nodeVal = trim($('#'+nodeId).val());
	if (nodeVal == "") return true;
	return false;
}
//check if value of given id is valid email
function isEmail(nodeId){
	var nodeVal = ($('#'+nodeId).val());
	return /^([_a-zA-Z0-9]+)(\.[_a-zA-Z0-9-]+)*@([a-zA-Z0-9-]+)(\.[a-zA-Z0-9-]+)*(\.[a-z]{2,4})$/.test(nodeVal);
}
function trim(stringToTrim){
 	stringToTrim = stringToTrim.replace(/^\s+|\s+$/g,"");
 	stringToTrim = stringToTrim.replace(/\r\n/g,"");
 	stringToTrim = stringToTrim.replace(/\r/g,"");
 	return stringToTrim.replace(/\n/g,"");
}

function isEqual(nodeId1, nodeId2){
	var nodeVal1 = ($('#'+nodeId1).val());
	var nodeVal2 = ($('#'+nodeId2).val());
	if (nodeVal1 == nodeVal2) return true;
	else return false;
}