<?php
class cache
{
private static $_instance = null;
protected $_options = array(
'cache_dir' => "./",
'file_name_prefix' => 'cache',
'mode' => '1', //mode 1 为serialize model 2为保存为可执行文件
);
/**
* 得到本类实例
*
* @return Ambiguous
*/
public static function getInstance()
{
if(self::$_instance === null)
{
self::$_instance = new self();
}
return self::$_instance;
}
/**
* 得到缓存信息
*
* @param string $id
* @return boolean|array
*/
public static function get($id)
{
$instance = self::getInstance();
//缓存文件不存在
if(!$instance->has($id))
{
return false;
}
$file = $instance->_file($id);
$data = $instance->_fileGetContents($file);
if($data['expire'] == 0 || time() < $data['expire'])
{
return $data['contents'];
}
return false;
}
/**
* 设置一个缓存
*
* @param string $id 缓存id
* @param array $data 缓存内容
* @param int $cacheLife 缓存生命 默认为0无限生命
*/
public static function set($id, $data, $cacheLife = 0)
{
$instance = self::getInstance();
$time = time();
$cache = array();
$cache['contents'] = $data;
$cache['expire'] = $cacheLife === 0 ? 0 : $time + $cacheLife;
$cache['mtime'] = $time;
$file = $instance->_file($id);
return $instance->_filePutContents($file, $cache);
}
/**
* 清除一条缓存
*
* @param string cache id
* @return void
*/
public static function delete($id)
{
$instance = self::getInstance();
if(!$instance->has($id))
{
return false;
}
$file = $instance->_file($id);
//删除该缓存
return unlink($file);
}
/**
* 判断缓存是否存在
*
* @param string $id cache_id
* @return boolean true 缓存存在 false 缓存不存在
*/
public static function has($id)
{
$instance = self::getInstance();
$file = $instance->_file($id);
if(!is_file($file))
{
return false;
}
return true;
}
/**
* 通过缓存id得到缓存信息路径
* @param string $id
* @return string 缓存文件路径
*/
protected function _file($id)
{
$instance = self::getInstance();
$fileNmae = $instance->_idToFileName($id);
return $instance->_options['cache_dir'] . $fileNmae;
}
/**
* 通过id得到缓存信息存储文件名
*
* @param $id
* @return string 缓存文件名
*/
protected function _idToFileName($id)
{
$instance = self::getInstance();
$prefix = $instance->_options['file_name_prefix'];
return $prefix . '---' . $id;
}
/**
* 通过filename得到缓存id
*
* @param $id
* @return string 缓存id
*/
protected function _fileNameToId($fileName)
{
$instance = self::getInstance();
$prefix = $instance->_options['file_name_prefix'];
return preg_replace('/^' . $prefix . '---(.*)$/', '$1', $fileName);
}
/**
* 把数据写入文件
*
* @param string $file 文件名称
* @param array $contents 数据内容
* @return bool
*/
protected function _filePutContents($file, $contents)
{
if($this->_options['mode'] == 1)
{
$contents = serialize($contents);
}
else
{
$time = time();
$contents = "<?phpn".
" // mktime: ". $time. "n".
" return ".
var_export($contents, true).
"n?>";
}
$result = false;
$f = @fopen($file, 'w');
if ($f) {
@flock($f, LOCK_EX);
fseek($f, 0);
ftruncate($f, 0);
$tmp = @fwrite($f, $contents);
if (!($tmp === false)) {
$result = true;
}
@fclose($f);
}
@chmod($file,0777);
return $result;
}
/**
* 从文件得到数据
*
* @param sring $file
* @return boolean|array
*/
protected function _fileGetContents($file)
{
if(!is_file($file))
{
return false;
}
if($this->_options['mode'] == 1)
{
$f = @fopen($file, 'r');
@$data = fread($f,filesize($file));
@fclose($f);
return unserialize($data);
}
else
{
return include $file;
}
}
/**
* 构造函数
*/
protected function __construct()
{
}
/**
* 设置缓存路径
*
* @param string $path
* @return self
*/
public static function setCacheDir($path)
{
$instance = self::getInstance();
if (!is_dir($path)) {
exit('file_cache: ' . $path.' 不是一个有效路径 ');
}
if (!is_writable($path)) {
exit('file_cache: 路径 "'.$path.'" 不可写');
}
$path = rtrim($path,'https://www.jb51.net/') . 'https://www.jb51.net/';
$instance->_options['cache_dir'] = $path;
return $instance;
}
/**
* 设置缓存文件前缀
*
* @param srting $prefix
* @return self
*/
public static function setCachePrefix($prefix)
{
$instance = self::getInstance();
$instance->_options['file_name_prefix'] = $prefix;
return $instance;
}
/**
* 设置缓存存储类型
*
* @param int $mode
* @return self
*/
public static function setCacheMode($mode = 1)
{
$instance = self::getInstance();
if($mode == 1)
{
$instance->_options['mode'] = 1;
}
else
{
$instance->_options['mode'] = 2;
}
return $instance;
}
/**
* 删除所有缓存
* @return boolean
*/
public static function flush()
{
$instance = self::getInstance();
$glob = @glob($instance->_options['cache_dir'] . $instance->_options['file_name_prefix'] . '--*');
if(empty($glob))
{
return false;
}
foreach ($glob as $v)
{
$fileName = basename($v);
$id = $instance->_fileNameToId($fileName);
$instance->delete($id);
}
return true;
}
}
/* 初始化设置cache的配置信息什么的 */
cache::setCachePrefix('core'); //设置缓存文件前缀
cache::setCacheDir('./cache'); //设置存放缓存文件夹路径
//模式1 缓存存储方式
//a:3:{s:8:"contents";a:7:{i:0;i:1;i:1;i:2;i:2;i:3;i:3;i:34;i:4;i:5;i:5;i:6;i:6;i:6;}s:6:"expire";i:0;s:5:"mtime";i:1318218422;}
//模式2 缓存存储方式
/*
<?php
// mktime: 1318224645
return array (
'contents' =>
array (
0 => 1,
1 => 2,
2 => 3,
3 => 34,
4 => 5,
5 => 6,
6 => 6,
),
'expire' => 0,
'mtime' => 1318224645,
)
?>
*
*
*/
cache::setCacheMode('2');
if(!$row = cache::get('zj2'))
{
$array = array(1,2,3,34,5,6,6);
$row = cache::set('zj2',$array);
}
// cache::flush(); 清空所有缓存
print_r($row);
文件缓存 class
复制代码 代码如下: