protected function sanitizeFileName($name)
    {
        if ($this->sanitizerCallback) {
            return call_user_func($this->sanitizerCallback, $name);
        }
        return preg_replace('/[^A-Za-z0-9\.]+/', '_', $name);
    }
protected function sanitizeFileName($name)
    {
        if ($this->sanitizerCallback) {
            return call_user_func($this->sanitizerCallback, $name);
        }
        return preg_replace('/[^A-Za-z0-9\.]+/', '_', $name);
    }
protected function sanitizeFileName ( $ name ) { if ( $ this -> sanitizerCallback ) { return call_user_func ( $ this -> sanitizerCallback , $ name ) ; } return preg_replace ( '/[^A-Za-z0-9\.]+/' , '_' , $ name ) ; }
Sanitize the name of the uploaded file by stripping away bad characters
and replacing "invalid" characters with underscore _

@param  string $name
@return string
Sanitize the name of the uploaded file by stripping away bad characters and replacing invalid characters with underscore _