PHP缓存之文件缓存

2、PHP文件缓存的简单案例

_cache_path = $config['cache_path'];		}		else		{		   $this->_cache_path = realpath(dirname(__FILE__)."/")."/cache/";		}	}//判断key值对应的文件是否存在，如果存在，读取value值，value以序列化存储	public function get($id)	{		if ( ! file_exists($this->_cache_path.$id))		{			return FALSE;		}				$data = @file_get_contents($this->_cache_path.$id);		$data = unserialize($data);				if(!is_array($data) || !isset($data['time']) || !isset($data['ttl']))		{			return FALSE;		}				if ($data['ttl'] > 0 && time() >  $data['time'] + $data['ttl'])		{			@unlink($this->_cache_path.$id);			return FALSE;		}				return $data['data'];	}//设置缓存信息，根据key值，生成相应的缓存文件	public function set($id, $data, $ttl = 60)	{				$contents = array(				'time'		=> time(),				'ttl'		=> $ttl,							'data'		=> $data			);				if (@file_put_contents($this->_cache_path.$id, serialize($contents)))		{			@chmod($this->_cache_path.$id, 0777);			return TRUE;					}		return FALSE;	}//根据key值，删除缓存文件	public function delete($id)	{		return @unlink($this->_cache_path.$id);	}	public function clean()	{      $dh = @opendir($this->_cache_path);	   if(!$dh)         return FALSE;            while ($file = @readdir($dh))      {         if($file == "." || $file == "..")            continue;                  $path = $this->_cache_path."/".$file;         if(is_file($path))            @unlink($path);      }      @closedir($dh);      		return TRUE;	}}