src/PHPDish/Bundle/AdminBundle/Grid/Twig/GridExtension.php
protected function hasBlock($name)
    {
        foreach ($this->templates as $template) {
            if ($template->hasBlock($name)) {
                return true;
            }
        }
        return false;
    }
protected function hasBlock($name)
    {
        foreach ($this->templates as $template) {
            if ($template->hasBlock($name)) {
                return true;
            }
        }
        return false;
    }
是否有block

@param string $name
@return bool