Semi-dynamic Doctrine2 search function

Doctrin2Search.php

<?php
function searchCriteria($criteria){
            
            $cleanCritera = array();
            foreach($criteria as $key => $value){
                if( isset( $this->_class->fieldNames[$key] ) && !empty($value) ){
                    $cleanCritera[$key] = $value;
                }                
            }
            if(empty($cleanCritera)){
                return null;
            }
            $queryBuilder = $this->_em->createQueryBuilder();
            /**
             *@note example of partial requests, loads up a graph of Student proxies, if you ask for a field outside of the select
             *criteria, Doctrine2 will make a SQL query for that specific entity.
             */
            $entityAlias = "srcEnt";
            $queryBuilder->select("partial {$entityAlias}.{id, /REDACTED/, name_last, name_first, name_middle}")->from("{$this->_class->name}", $entityAlias );
            //andx is used to build a WHERE clause like (expression 1 AND expression 2)
            //Alternatively you can use orx for (expression 1 OR expression 2)
            //Also you can next either inside of each other...so ->where(andx(orx("expression1","expression2),"expression3"))
            //would be WHERE ( ( expression 1 OR expression 2 ) AND expression 3  )
            $or = $queryBuilder->expr()->andx();
            /**
             *@note Example of programmatic Doctrine2 Like expression
             */
            foreach($cleanCritera as $key => $value){
                $or->add($queryBuilder->expr()->like("{$entityAlias}.{$key}", ":{$key}" ));                
                $queryBuilder->setParameter($key, "%{$value}%");
            }
            $queryBuilder->where($or);
            
            return $queryBuilder->getQuery()->getResult();            
        }