// +----------------------------------------------------------------------
// |缓存类
// +----------------------------------------------------------------------
// | Author: justmepzy(justmepzy@gmail.com)
// +----------------------------------------------------------------------
class Cache{
//提示信息
public $tip_message;
//缓存目录
protected $cache_dir;
//缓存文件名
private $cache_file_name;
//缓存文件后缀
private $cache_file_suffix;
public function __construct($dir,$cache_file_suffix ='.php'){
$this->cache_dir = isset($dir)?$dir:dirname(__FILE__).DIRECTORY_SEPARATOR.'default_cache_data';
$this->cache_file_suffix =$cache_file_suffix;
if(!$this->dir_isvalid($this->cache_dir)){
die($this->tip_message);//创建目录失败
}
}
// +----------------------------------------------------------------------
// |添加一个值，如果已经存在，则返回false,写入文件失败返回false
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
public function add($cache_key,$cache_value,$life_time=1800){
if(file_exists($this->get_cache_file_name($cache_key))){
$this->tip_message ='缓存数据已存在.';
return false;
}
$cache_data['data'] =$cache_value;
$cache_data['life_time'] =$life_time;
//以JSON格式写入文件
if(file_put_contents($this->get_cache_file_name($cache_key), json_encode($cache_data))){
return true;
}else{
$this->tip_message ='写入缓存失败.';
return false;
}
}
// +----------------------------------------------------------------------
// |添加一个值，如果已经存在，则覆写
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
public function set($cache_key,$cache_value,$life_time=1800){
$cache_data['data'] =$cache_value;
$cache_data['life_time'] =$life_time;
if(file_put_contents($this->get_cache_file_name($cache_key), json_encode($cache_data))){
return true;
}else{
$this->tip_message ='写入缓存失败.';
return false;
}
}
// +----------------------------------------------------------------------
// |获取一个key值
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
public function get($cache_key){
if(!file_exists($this->get_cache_file_name($cache_key))){
return false;
}
$data =$this->object_to_array(json_decode(file_get_contents($this->get_cache_file_name($cache_key))));
if($this->check_isvalid($data['life_time'])){
unset($data['life_time']);
return $data['data'];
}else{
unlink($this->cache_file_name);
$this->tip_message ='数据已过期.';
return false;
}
}
// +----------------------------------------------------------------------
// |删除一个key值
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
public function delete($cache_key){
if(file_exists($this->get_cache_file_name($cache_key))){
if(unlink($this->get_cache_file_name($cache_key)))
return true;
else
return false;
}else{
$this->tip_message ='文件不存在.';
return true;
}
}
// +----------------------------------------------------------------------
// |清除所有缓存文件
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
public function flush(){
$this->delete_file($this->cache_dir);
}
// +----------------------------------------------------------------------
// |自动清除过期文件
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
public function auto_delete_expired_file(){
$this->delete_file($this->cache_dir,false);
}
// +----------------------------------------------------------------------
// |检查目录是否存在,不存在则创建
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
private function dir_isvalid($dir){
if (is_dir($dir))
return true;
try {
mkdir($dir,0777);
}catch (Exception$e) {
$this->tip_message ='所设定缓存目录不存在并且创建失败!请检查目录权限!';
return false;
}
return true;
}
// +----------------------------------------------------------------------
// |检查有效时间
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
private function check_isvalid($expired_time = 0) {
//if(!file_exists($this->cache_file_name)) return false;
if (!(@$mtime =filemtime($this->cache_file_name)))return false;
if (time() -$mtime >$expired_time)return false;
return true;
}
// +----------------------------------------------------------------------
// |获得缓存文件名
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
private function get_cache_file_name($key){
$this->cache_file_name =$this->cache_dir.DIRECTORY_SEPARATOR.md5($key).$this->cache_file_suffix;
return $this->cache_file_name;
}
// +----------------------------------------------------------------------
// |object对象转换为数组
// +----------------------------------------------------------------------
// |
// +----------------------------------------------------------------------
protected function object_to_array($obj){
$_arr =is_object($obj) ? get_object_vars($obj) :$obj;
foreach ($_arr as $key =>$val) {
$val = (is_array($val) ||is_object($val)) ? object_to_array($val) :$val;
$arr[$key] =$val;
}
return $arr;
}
// +----------------------------------------------------------------------
// |删除目录下的所有文件
// +----------------------------------------------------------------------
// | $mode true删除所有 false删除过期
// +----------------------------------------------------------------------
protected function delete_file($dir,$mode=true) {
$dh=opendir($dir);
while ($file=readdir($dh)) {
if($file!="." &&$file!="..") {
$fullpath=$dir."/".$file;
if(!is_dir($fullpath)) {
if($mode){
unlink($fullpath);
}else{
$this->cache_file_name =$fullpath;
if(!$this->get_isvalid_by_path($fullpath)) unlink($fullpath);
}
}else {
delete_file($fullpath,$mode);
}
}
}
closedir($dh);
}
private function get_isvalid_by_path($path){
$data =$this->object_to_array(json_decode(file_get_contents($path)));
return $this->check_isvalid($data['life_time']);
}
}
?>
摘抄笔记)
