php 缓存文件入门程序_PHP教程

class PageCache {

/**
* @var string $file 缓存文件地址
* @access public
*/
public $file;

/**
* @var int $cacheTime 缓存时间
* @access public
*/
public $cacheTime = 3600;

/**
* 构造函数
* @param string $file 缓存文件地址
* @param int $cacheTime 缓存时间
*/
function __construct($file, $cacheTime = 3600) {
$this->file = $file;
$this->cacheTime = $cacheTime;
}

/**
* 取缓存内容
* @param bool 是否直接输出，true直接转到缓存页,false返回缓存内容
* @return mixed
*/
public function get($output = true) {
if (is_file($this->file) && (time()-filemtime($this->file))<=$this->cacheTime && !$_GET['nocache']) {
if ($output) {
header('location:' . $this->file);
exit;
} else {
return file_get_contents($this->file);
}
} else {
return false;
}
}

/**
* 设置缓存内容
* @param $content 内容html字符串
*/
public function set($content) {
$fp = fopen($this->file, 'w');
fwrite($fp, $content);
fclose($fp);
}
}