PHP缓冲ob_start和页面文件缓存

2 内容 

3 echo ob_get_contents() ;

$value = $cache->put('data_key', 'data_value');完整实例：

$cache = new Cache();

//从缓存从读取键值 $key 的数据
$values = $cache->get($key);

//如果没有缓存数据
if ($values == false) {
 //insert code here...
 //写入键值 $key 的数据
 $cache->put($key, $values);
} else {
 //insert code here...
}
Cache.class.php

<?php
class Cache {
 private $cache_path;//path for the cache
 private $cache_expire;//seconds that the cache expires

 //cache constructor, optional expiring time and cache path
 public function Cache($exp_time=3600,$path="cache/"){
  $this->cache_expire=$exp_time;
  $this->cache_path=$path;
 }

 //returns the filename for the cache
 private function fileName($key){
  return $this->cache_path.md5($key);
 }

 //creates new cache files with the given data, $key== name of the cache, data the info/values to store
 public function put($key, $data){
  $values = serialize($data);
  $filename = $this->fileName($key);
  $file = fopen($filename, 'w');
     if ($file){//able to create the file
         fwrite($file, $values);
         fclose($file);
     }
     else return false;
 }

 //returns cache for the given key
 public function get($key){
  $filename = $this->fileName($key);
  if (!file_exists($filename) || !is_readable($filename)){//can't read the cache
   return false;
  }
  if ( time() < (filemtime($filename) + $this->cache_expire) ) {//cache for the key not expired
   $file = fopen($filename, "r");// read data file
         if ($file){//able to open the file
             $data = fread($file, filesize($filename));
             fclose($file);
             return unserialize($data);//return the values
         }
         else return false;
  }
  else return false;//was expired you need to create new
  }
}
?>