静态缓存设置缓存失效时间

将缓存时间存入静态缓存文件,拼装时间

$cacheTime = sprintf("%011d",$cacheTime);
return file_put_contents($filename,$cacheTime.json_encode($value));

判断失效时间：

$contents  = file_get_contents($filename);
$cacheTime = (int) substr($contents,0,11);
$value 	   = substr($contents,11);
if($cacheTime != 0 && $cacheTime + filemtime($filename) < time()){
	unlink($filename);
	return FALSE;
}

如果过期则删除静态缓存文件

写入缓存的时候记得判断缓存是否存在：

if(!$contents = $cache->cacheData('index_cache'.$page.'-'.$pagesize))