为啥smarty循环fetch的话，每次内容都一样

<br />foreach ( $category as $c ) {<br />	$products = $util->getArrayByQueryString ( "select * from product_detail where sid=$c[id]" );<br />	$smarty->assign ( "html_title", $c [name] . '：所有子类产品' );<br />	$smarty->assign ( "products", $products );<br />//	foreach ( $products as $p ) {<br />//		echo $p [id] . $p [name] . '<br/>';<br />//	}<br />	$content = $smarty->fetch ( "products.tpl" );<br />	$file_name = './products/' . $c [id] . '.html';<br />	//html生成<br />	create_html ( $file_name, $content );<br />}<br />