php 文件式缓存类[转]

php操作IO的速度很快，估计是直接调用C的函数，拿来做缓存是不错的，CMS有大量类似的应用。

include目录config.php：

1 define('ROOT_PATH', str_replace('include/config.php', '', str_replace('\\', '/', __FILE__)));

library目录 cls_filecache.php：

 1 <?php
 2 define('ROOT_PATH', str_replace('library/index.php', '', str_replace('\\', '/', __FILE__)));
 3 require_once ROOT_PATH.'include/config.php';
 4 class FileCache{
 5     var $path='';
 6     static $cache;
 7     public function __construct($folder='caches') {
 8         $this->path=ROOT_PATH.$folder;
 9         if(!is_dir(ROOT_PATH.$folder)){
10             mkdir(ROOT_PATH.$folder);
11         }
12     }
13     //添加/修改缓存
14     function add($key,$val){
15         //echo FileCache::$cache;
16         //FileCache::$cache['test']='asdqew';
17         $cachefile=$this->path.'/'.$key.'.php';
18         $content = '<?php ';
19         $content .= '$data = ' . var_export($val, true) .'; ';
20         $content .= '?>';
21         file_put_contents($cachefile, $content, LOCK_EX);
22     }
23     //获取缓存
24     function get($key){
25         //echo FileCache::$cache[$key];
26         if(!is_null(FileCache::$cache[$key])){
27             return FileCache::$cache[$key];
28         }
29         $cache_file_path = $this->path.'/'.$key.'.php';
30         if (file_exists($cache_file_path))
31         {
32             include_once($cache_file_path);
33             //echo $data;
34             FileCache::$cache[$key] = $data;
35             //echo FileCache::$cache[$key];
36             return FileCache::$cache[$key];
37         }
38         else
39         {
40             return false;
41         }
42     }
43     //删除缓存
44     function delete($key){
45         //echo FileCache::$cache[$key]=null;
46         if(is_dir($this->path)){
47             if(file_exists($this->path.'/'.$key.'.php')){
48                 if(unlink($this->path.'/'.$key.'.php')){
49                     FileCache::$cache[$key]=null;
50                     return true;
51                 }else{
52                     return false;
53                 }
54             }else{
55                 return true;
56             }
57         }else{
58             return true;
59         }
60     }
61     //删除所有缓存
62     function deleteAll(){
63         if(is_dir($this->path)){
64             $dir=opendir($this->path);
65             while(false!==($file=readdir($dir))){
66                 $files[]=$file;
67             }
68             closedir($dir);
69             if($files){//文件夹不为空,包括 . 和 ..2个特殊文件夹
70                 $isdel=true;
71                 foreach($files as $f){
72                     if($f!='.' && $f!='..')
73                         $isdel=&unlink($this->path.'/'.$f);
74                 }
75                 if($isdel){
76                     FileCache::$cache=null;
77                 }
78                 return $isdel;
79             }else
80                 return false;
81         }
82     }
83 }
84 ?>

调用测试文件：

 1 <?php
 2 require_once 'include/config.php';
 3 require_once 'library/cls_filecache.php';
 4 $cache=new FileCache();
 5 $cache->add('test', 123);
 6 $cache->add('test', 'asd');
 7 echo $cache->get('test');
 8 echo $cache->get('test2');
 9 $cache->delete('test');
10 echo $cache->get('test');
11 echo $cache->get('test2');
12 $cache->deleteAll();
13 echo $cache->get('test');
14 echo $cache->get('test2');
15 ?>

转自：http://babyhey.com/forum.php?mod=viewthread&tid=165&extra=page%3D1