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The principle of sending a PHP cache class_PHP tutorial
- WBOYOriginal
- 2016-07-13 17:43:56899browse
define(CACHE_ROOT, dirname(__FILE__)./cache); //Cache storage directory
define(CACHE_TIME, 1800);//Cache time in seconds
define(CACHE_FIX,.html);
$CacheName=md5($_SERVER[REQUEST_URI]).CACHE_FIX; //Cache file name
$CacheDir=CACHE_ROOT./.substr($CacheName,0,1);//Cache file storage directory
$CacheUrl=$CacheDir./.$CacheName;//Full path of cache file
//The GET request is cached. After POST, you generally want to see the latest results
if($_SERVER[REQUEST_METHOD]==GET){
//If the cache file exists and has not expired, read it out.
if(file_exists($CacheName) && time()-filemtime($CacheName)
$fp=fopen($CacheName,rb);
fpassthru($fp);
fclose($fp);
exit;
}
// Determine whether the folder exists, create it if it does not exist
elseif(!file_exists($CacheDir)){
if(!file_exists(CACHE_ROOT)){
mkdir(CACHE_ROOT,0777);
chmod(CACHE_ROOT,0777);
}
mkdir($CacheDir,0777);
chmod($CacheDir,0777);
}
//Callback function, this function is automatically called when the program ends
function AutoCache($contents){
global $CacheUrl;
$fp=fopen($CacheUrl,wb);
fwrite($fp,$contents);
fclose($fp);
chmod($CacheUrl,0777);
//While generating a new cache, automatically delete all old caches to save space and can be ignored.
//DelOldCache();
return $contents;
}
function DelOldCache(){
chdir(CACHE_ROOT);
foreach (glob("*/*".CACHE_FIX) as $file){
if(time()-filemtime($file)>CACHE_TIME)unlink($file);
}
}
//Callback function auto_cache
ob_start(AutoCache);
}else{
//Delete the cache file if it is not a GET request.
if(file_exists($CacheUrl))unlink($CacheUrl);
}
?>
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