PHP的SimpleXML對象緩存

考慮下面的函數原型爲緩存對象從緩存RSS（XML）飼料：PHP的SimpleXML對象緩存

function cacheObject($xml,$name,$age = 3600) 
    { 
    // directory in which to store cached files 
    $cacheDir = "cache/"; 
    // cache filename 
    $filename = $cacheDir.$name; 
    // default to fetch the file 
    $cache = true; 
    // but if the file exists, don't fetch if it is recent enough 
    if (file_exists($filename)) 
    { 
     $cache = (filemtime($filename) < (time()-$age)); 
    } 
    // fetch the file if required 
    if ($cache) 
    { 
     $item = $xml->channel->item; 
     file_put_contents($filename,serialize($item)); 
     // update timestamp to now 
     touch($filename); 
    } 
    // return the cache filename 
    return unserialize(file_get_contents($filename)); 
    }

函數調用如下：

$urlD = "http://somerss.php"; 
    $xmlD = simplexml_load_file(cacheFetch($urlD,'cachedfeedD.xml',3600)); 
    $itemD = ''; 
    if($xmlD === FALSE) 
     {$itemD = '';} 
    else 
     {$itemD = cacheObject($xmlD,'cacheobjectD',3600);} 
$urlM = "somerss2.php"; 
    $xmlM = simplexml_load_file(cacheFetch($urlM,'cachedfeedM.xml',3600)); 
    $itemM = ''; 
    if($xmlM === FALSE) 
     {$itemM = '';} 
    else 
     {$itemM = cacheObject($xmlM,'cacheobjectM',3600);}

我得到以下錯誤：

Fatal error: Uncaught exception 'Exception' 
with message 'Serialization of 'SimpleXMLElement' is not allowed' in C:\xampp\htdocs\sitefinal\cacheObject.php:20 Stack trace: #0 C:\xampp\htdocs\sitefinal\cacheObject.php(20): serialize(Object(SimpleXMLElement))

任何幫助使這個程序的工作非常感謝。

來源

2011-10-17 George