


A simple and practical complete example of PHP cache class, simple and practical php cache_PHP tutorial
一个简洁实用的PHP缓存类完整实例,简洁实用php缓存
本文完整描述了一个简洁实用的PHP缓存类,可用来检查缓存文件是否在设置更新时间之内、清除缓存文件、根据当前动态文件生成缓存文件名、连续创建目录、缓存文件输出静态等功能。对于采用PHP开发CMS系统来说,离不开对缓存的处理,合理利用好缓存可有效的提高程序执行效率。
php缓存类文件完整代码如下:
<?php /* * 缓存类 cache */ class cache { //缓存目录 var $cacheRoot = "./cache/"; //缓存更新时间秒数,0为不缓存 var $cacheLimitTime = 0; //缓存文件名 var $cacheFileName = ""; //缓存扩展名 var $cacheFileExt = "php"; /* * 构造函数 * int $cacheLimitTime 缓存更新时间 */ function cache( $cacheLimitTime ) { if( intval( $cacheLimitTime ) ) $this->cacheLimitTime = $cacheLimitTime; $this->cacheFileName = $this->getCacheFileName(); ob_start(); } /* * 检查缓存文件是否在设置更新时间之内 * 返回:如果在更新时间之内则返回文件内容,反之则返回失败 */ function cacheCheck(){ if( file_exists( $this->cacheFileName ) ) { $cTime = $this->getFileCreateTime( $this->cacheFileName ); if( $cTime + $this->cacheLimitTime > time() ) { echo file_get_contents( $this->cacheFileName ); ob_end_flush(); exit; } } return false; } /* * 缓存文件或者输出静态 * string $staticFileName 静态文件名(含相对路径) */ function caching( $staticFileName = "" ){ if( $this->cacheFileName ) { $cacheContent = ob_get_contents(); ob_end_flush(); if( $staticFileName ) { $this->saveFile( $staticFileName, $cacheContent ); } if( $this->cacheLimitTime ) $this->saveFile( $this->cacheFileName, $cacheContent ); } } /* * 清除缓存文件 * string $fileName 指定文件名(含函数)或者all(全部) * 返回:清除成功返回true,反之返回false */ function clearCache( $fileName = "all" ) { if( $fileName != "all" ) { $fileName = $this->cacheRoot . strtoupper(md5($fileName)).".".$this->cacheFileExt; if( file_exists( $fileName ) ) { return @unlink( $fileName ); }else return false; } if ( is_dir( $this->cacheRoot ) ) { if ( $dir = @opendir( $this->cacheRoot ) ) { while ( $file = @readdir( $dir ) ) { $check = is_dir( $file ); if ( !$check ) @unlink( $this->cacheRoot . $file ); } @closedir( $dir ); return true; }else{ return false; } }else{ return false; } } /*根据当前动态文件生成缓存文件名*/ function getCacheFileName() { return $this->cacheRoot . strtoupper(md5($_SERVER["REQUEST_URI"])).".".$this->cacheFileExt; } /* * 缓存文件建立时间 * string $fileName 缓存文件名(含相对路径) * 返回:文件生成时间秒数,文件不存在返回0 */ function getFileCreateTime( $fileName ) { if( ! trim($fileName) ) return 0; if( file_exists( $fileName ) ) { return intval(filemtime( $fileName )); }else return 0; } /* * 保存文件 * string $fileName 文件名(含相对路径) * string $text 文件内容 * 返回:成功返回ture,失败返回false */ function saveFile($fileName, $text) { if( ! $fileName || ! $text ) return false; if( $this->makeDir( dirname( $fileName ) ) ) { if( $fp = fopen( $fileName, "w" ) ) { if( @fwrite( $fp, $text ) ) { fclose($fp); return true; }else { fclose($fp); return false; } } } return false; } /* * 连续建目录 * string $dir 目录字符串 * int $mode 权限数字 * 返回:顺利创建或者全部已建返回true,其它方式返回false */ 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; } } ?>
使用该缓存类的时候可将以上代码保存为cache.php,具体用法如下所示:
include( "cache.php" ); $cache = new cache(30); $cache->cacheCheck(); echo date("Y-m-d H:i:s"); $cache->caching();
一种是对 页面结果的缓存 应用服务器级别的 软件如 squid
一种是 内存级别的 一般是对 php 频繁调用的并且如果每次查询会消耗大量资源的数据 软件有 memcached
一种是 对php 程序进行优化编码的缓存 如 apache 里面的 apc, eAccelerator, XCache 等
还有一种就是文件缓存 这种一般是 用php自己实现的 没什么可说的.
看你的具体需求是怎样的了..有疑问 请联系 1465663870
//以下是缓存类:
class cache {
//缓存目录
var $cacheRoot = "./cache/";
//缓存更新时间秒数,0为不缓存
var $cacheLimitTime = 0;
//缓存文件名
var $cacheFileName = "";
//缓存扩展名
var $cacheFileExt = "html";
/*
* 构造函数
* int $cacheLimitTime 缓存更新时间
*/
function cache( $cacheLimitTime ) {
if( intval( $cacheLimitTime ) )
$this->cacheLimitTime = $cacheLimitTime;
$this->cacheFileName = $this->getCacheFileName();
//echo $this->cacheFileName;
ob_start();
}
/*
* 检查缓存文件是否在设置更新时间之内
* 返回:如果在更新时间之内则返回文件内容,反之则返回失败
*/
function cacheCheck(){
if( file_exists( $this->cacheFileName ) ) {
$cTime = $this->getFileCreateTime( $this->cacheFileName );
if( $cTime + $this->cacheLimitTime > time() ) {
echo file_get_contents( $this->cacheFileName );
ob_end_flush();
exit;
}
}
return false;
}
/*
* 缓存文件或者输出静态
* string $staticFileName 静态文件名(含相对路径)
*/
function caching( $staticFileName = "" ){
if( $this->cacheFileName ) {
$cacheContent = ob_get_contents();
//echo $cacheContent;
ob_end_flush();
if( $staticFileName ) {
$this->saveFile( $staticFileName, $cacheContent );
}
if( $this->cacheLimitTime )
$this->saveFile( $this->cacheFileName, $cacheContent );
}
}
/*
......余下全文>>

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