protected function getKeyOrNull($model)
    {
        if ($model == null) {
            return null;
        }
        return $model->{self::ROW_NUM_COLUMN} ?: ($model instanceof Model ? $model->getKey() : null);
    }
protected function getKeyOrNull($model)
    {
        if ($model == null) {
            return null;
        }
        return $model->{self::ROW_NUM_COLUMN} ?: ($model instanceof Model ? $model->getKey() : null);
    }
protected function getKeyOrNull ( $ model ) { if ( $ model == null ) { return null ; } return $ model -> { self :: ROW_NUM_COLUMN } ? : ( $ model instanceof Model ? $ model -> getKey ( ) : null ) ; }
Try to get model row number or key. Return row number column if exists.
Try to get model row number or key . Return row number column if exists .