public function findByKey($target, $default = '')
    {
        foreach ($this->collection as $group => $hashMap) {
            if (array_key_exists($target, $hashMap)) {
                return $hashMap[$target];
            }
        }

        return $default;
    }
public function findByKey($target, $default = '')
    {
        foreach ($this->collection as $group => $hashMap) {
            if (array_key_exists($target, $hashMap)) {
                return $hashMap[$target];
            }
        }

        return $default;
    }
public function findByKey ( $ target , $ default = '' ) { foreach ( $ this -> collection as $ group => $ hashMap ) { if ( array_key_exists ( $ target , $ hashMap ) ) { return $ hashMap [ $ target ] ; } } return $ default ; }
Find a value by its associated key

@param string $key
@param mixed $default Default value to be returned
@return mixed
Find a value by its associated key