File caching implementation program code in php_PHP tutorial

File caching means to generate a file from the cache. This file can be a php, txt, etc. file. When I download and access it, I will judge the last generation time of the access. If it exceeds the time we specified, it will be generated again. Otherwise, it will be generated directly. Call the cache file, which can reduce the query to the mysql database.

File caching principle

1. Serialize the data that needs to be cached through the serialize function and save it directly to the file. When you need to use cached data, read the file content through deserialization and copy it to the required variables, and then use it. Data that changes infrequently can be written to the cache file.

File cache example

index.php

The code is as follows

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代码如下

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define('CACHE_ROOT','./');  include_once('./cache.func.php');  $file = 'qzp';  $cacheFile = getCacheFileByID($file,'info/');    print_R(readCache($cacheFile));    $info = array(       'username'=>'qzp',       'area_name'=>'admin',       'mp_name'=>'1234',       'gh_name'=>'5678'); writeCache($cacheFile,$info); cache.func.php文件  function arrayeval($array, $level = 0) {     $space = '';     for($i = 0; $i <= $level; $i++) { $space .= "t"; } $evaluate = "Arrayn$space(n"; $comma = $space; foreach($array as $key => $val) {         $key = is_string($key) ? '''.addcslashes($key, ''').''' : $key;         $val = !is_array($val) && (!preg_match("/^-?[1-9]d*$/", $val) || strlen($val) > 12) ? '''.addcslashes($val, ''').''' : $val;         if(is_array($val)) {             $evaluate .= "$comma$key => ".arrayeval($val, $level + 1);         } else {             $evaluate .= "$comma$key => $val";         }         $comma = ",n$space";     }     $evaluate .= "n$space)";     return $evaluate; }   function getCacheFileByID($id,$pre='info/',$md5=true){  if($md5){   $md5id = md5($id);   return CACHE_ROOT.'/'.$pre.substr($md5id,0,2).'/'.substr($md5id,2,2).'/'.$id;  }else{   return CACHE_ROOT.'/'.$pre.$id;  } }   function readCache($filename,$time=0){  if($datas = @file_get_contents($filename)){   $datas = unserialize($datas);   if($time < 1 || (time() - $datas['time'] < $time)){ return $datas['data']; } } return false; } function writeCache($filename,$data){ makeDir(dirname($filename)); if($handle = fopen($filename,'w+')){ $datas = array('data'=>$data,'time'=>time());   flock($handle,LOCK_EX);   $rs = fputs($handle,serialize($datas));   flock($handle,LOCK_UN);   fclose($handle);   if($rs!==false){    return true;   }  }  return false; }   function makeDir($path) {  if (! file_exists ( $path )) {   makeDir ( dirname ( $path ) );   if (! mkdir ( $path, 0777 ))   die ( '无法创建文件夹' . $path );  } }

define('CACHE_ROOT','./'); include_once('. /cache.func.php'); $file = 'qzp'; $cacheFile = getCacheFileByID($file,'info/'); print_R(readCache($cacheFile)) ; $info = array( 'username'=>'qzp', 'area_name'=>'admin', 'mp_name'=>'1234' , 'gh_name'=>'5678');writeCache($cacheFile,$info);cache.func.php file function arrayeval($array , $level = 0) { $space = ''; for($i = 0; $i <= $level; $i++) {<🎜> $space .= "t";< 🎜> }<🎜> $evaluate = "Arrayn$space(n";<🎜> $comma = $space;<🎜> foreach($array as $key => $val) { $key = is_string ($key) ? '''.addcslashes($key, ''').''' : $key;            $val = !is_array($val) && (!preg_match("/^-?[1 -9]d*$/", $val) || strlen($val) > 12) ? '''.addcslashes($val, ''').''' : $val; If( is_array($val)) {                $evaluate .= "$comma$key => ".arrayeval($val, $level + 1);                                                                                                      comma$key => $val"; } } evaluate;} function getCacheFileByID($id,$pre='info/',$md5=true){ if($md5){ $md5id = md5($ id); return CACHE_ROOT.'/'.$pre.substr($md5id,0,2).'/'.substr($md5id,2,2).'/'.$id; }else{ return CACHE_ROOT.'/'.$pre.$id; }} function readCache($filename,$time=0){ if( $datas = @file_get_contents($filename)){ $datas = unserialize($datas); if($time < 1 || (time() - $datas['time'] < $ time)){<🎜> return $datas['data'];<🎜> }<🎜> }<🎜> return false;<🎜>}<🎜> <🎜>function writeCache($filename,$data){ <🎜> makeDir(dirname($filename));<🎜> if($handle = fopen($filename,'w+')){<🎜> $datas = array('data'=>$data,'time '=>time()); flock($handle,LOCK_EX); $rs = fputs($handle,serialize($datas)); flock($handle,LOCK_UN); fclose($handle); if($rs!==false){ return true; } } return false;} function makeDir($path){ if (! file_exists ( $path )) { makeDir ( dirname ( $path ) ); if (! mkdir ( $path, 0777 )) die ( 'Unable to create folder' . $path ); }}

Serialize and store the files to be cached, and deserialize them when used.

Use smarty, a tool for caching PHP template data. smarty caches HTML files into a static HTML page. You can use smarty for template files that need to be cached.
Example:

The code is as follows

代码如下	复制代码
//包含Smarty类库 require('libs/Smarty.class.php'); //创建Smarty类的对象 $smarty = new Smarty; //启用缓存 $smarty->caching = true;   //指定缓存文件保存的目录 $smarty->cache_dir = "./cache/";   //也会把输出保存 $smarty->display('index.tpl') ?>

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//Contains Smarty class library

require('libs/Smarty.class.php');

//Create Object of Smarty class$smarty = new Smarty; //Enable caching$smarty->caching = true; //Specify the directory where cache files are saved$smarty->cache_dir = "./cache/"; //The output will also be saved$smarty->display('index.tpl')?> ;

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