以文件形式缓存php变量的方法

本文实例讲述了以文件形式缓存php变量的方法。分享给大家供大家参考。具体实现方法如下

本文实例讲述了以文件形式缓存php变量的方法。分享给大家供大家参考。具体实现方法如下：

<?php
/*
$cache_set = array(
//缓存路径 , 最后要加"/"
'cacheRoot'=>'./cache/',
//缓存时间
'cacheTime'=>20,
//cache type
'cacheType'=>1,
//扩展名
'cacheExe'=>'.php'
);
$cache = new Cache($cache_set);
$a=array('1','2');
$a="aaa";
$b='';
if($cache->cache_is("d")){
 $c=$cache->cache_read("d");
 echo "c";
 print_r($c);
}else {
$b=$cache->cache_data('d',$a);
}
print_r($b);
//$cache->clear("a");
//echo $cache->cache_read("./cache/d.php");
//echo $d;
*/
/**
 * 数据缓存类 v1.0
 * @author shooke
 * 2009-11-13 16:02:26
 * 用于缓存数据,如变量,但不能缓存页面
 */
class Cache{
 //配置
 public $config = array(
 //缓存路径
 'cacheRoot'=>'./cache/',
 //缓存时间
 'cacheTime'=>1,
 //cache 类型 1串化数据 2变量
 'cacheType'=>2,
 //扩展名
 'cacheExe'=>'.php'
 //转换中间变量
 );
 public $return_name=array();
 function __construct($cache_set = array())
 {
 if(!empty($cache_set)) $this->config=array_merge($this->config,$cache_set);
 $this->config['ClassName'] = __CLASS__;
 }
 public function clear($filename=''){
 if (file_exists($this->cache_file($filename))) {
 @unlink($this->cache_file($filename));
 }elseif (empty($filename)){
 $this->clear_dir($this->config['cacheRoot']);
 }else{
 $this->clear_dir($this->config['cacheRoot'].$filename);
 echo $this->config['cacheRoot'].$filename;
 }
 }
 //循环删除路径
 private function clear_dir($dir,$to = false)
 {
 if ($list = glob($dir.'/*'))
 {
 foreach ($list as $file)
 {
 is_dir($file) ? $this->clear_dir($file) : unlink($file);
 }
 }
 if ($to === false) rmdir($dir);
 }
 //写入缓存
 private function cache_write($filename, $writetext, $openmod='w'){
 if (!file_exists($filename)) {
 @$this->makeDir( dirname($filename ));
 }
 if(@$fp = fopen($filename, $openmod)) {
 flock($fp, 2);
 fwrite($fp, $writetext);
 fclose($fp);
 return true;
 } else {
 echo "File: $filename write error.";
 return false;
 }
 }
 //缓存有效期 有效返回 true
 public function cache_is($fileName){
 $fileName=$this->cache_file($fileName);
 if( file_exists( $fileName ) ) {
 //如果缓存时间为负数则永不过期
 if ($this->config['cacheTime'] < 0) {
 return true;
 }
 //如果缓存时间为0则一直过期
 if ($this->config['cacheTime'] == 0) {
 return false;
 }
 //获取缓存文件的建立时间
 $ctime = intval(filemtime( $fileName ));
 //比较是否大于缓存时间,是则过期 否则不过期
 if (time() - $ctime > $this->config['cacheTime']) {
 return false;
 }else {
 return true;
 }
 //文件不存在视为过期失效
 }else {
 return false;
 }
 }
 public function cache_data($name,$data){
 $varname=$name;
 $name = $this->cache_file($name);
 //config['cacheTime']==0也就是不启用缓存是直接返回数据
 if ($this->config['cacheTime'] <> 0) {
 if($this->config['cacheType']==1){
 $write_data = "<?php exit;?>".serialize($data);
 //return $data;
 }else {
 $write_data = "<?php\\r\\n\\$var= ";
 $write_data .= var_export($data,true);
 $write_data .=";\\r\\n?>";
 }
 $this->cache_write($name,$write_data);
 }
 return $data;
 }
 //缓存文件名
 private function cache_file($filename){
 return $this->config['cacheRoot'].$filename.$this->config['cacheExe'];
 }
 //读取文件
 public function cache_read($file){
 $file=$this->cache_file($file);
 if (!file_exists($file)) {
 return '';
 }
 if($this->config['cacheType']==1){
 if (function_exists('file_get_contents')){
 $cache_Content= file_get_contents($file);
 }else{
 $fopen = fopen($file,'r');
 $cache_Content = '';
 do {
 $data = fread($fopen,filesize($file));
 if (strlen($data)===0) break;
 $cache_Content .= $data;
 }while(1);
 fclose($fopen);
 }
 $cache_Content = substr($cache_Content,13);/* 去除<?php exit;?> */
 $cache_Content = unserialize($cache_Content);
 return $cache_Content;
 }else{
 include_once($file);
 return $var;
 }
 }
 //循环创建目录
 private function makeDir( $dir, $mode = 0777 ) {
 if( ! $dir ) return 0;
 $dir = str_replace( "\\\\", "/", $dir );
 $mdir = "";
 foreach( explode( "/", $dir ) as $val ) {
 $mdir .= $val."/";
 if( $val == ".." || $val == "." || trim( $val ) == "" ) continue;
 if( ! file_exists( $mdir ) ) {
 if(!@mkdir( $mdir, $mode )){
 return false;
 }
 }
 }
 return true;
 }
}
?>

希望本文所述对大家的php程序设计有所帮助。