php 正则表达式的是一个使用范例 统计链接生成与替换

liuyuehua

<?php
class acmeCache{
function fetch($name, $refreshSeconds = 0){
if(!$GLOBALS['cache_active']) return false;
if(!$refreshSeconds) $refreshSeconds = 60;
$cacheFile = acmeCache::cachePath($name);
if(file_exists($cacheFile) and
((time()-filemtime($cacheFile))< $refreshSeconds))
$cacheContent = file_get_contents($cacheFile);
return $cacheContent;
}
function save($name, $cacheContent){
if(!$GLOBALS['cache_active']) return;
$cacheFile = acmeCache::cachePath($name);
acmeCache::savetofile($cacheFile, $cacheContent);
}
// for internal use
// ====================
function cachePath($name){
$cacheFolder = $GLOBALS['cache_folder'];
if(!$cacheFolder) $cacheFolder = trim($_SERVER['DOCUMENT_ROOT'],'/').'/cache/';
return $cacheFolder . md5(strtolower(trim($name))) . '.cache';
}
function savetofile($filename, $data){
$dir = trim(dirname($filename),'/').'/';
acmeCache::forceDirectory($dir);
$file = fopen($filename, 'w');
fwrite($file, $data); fclose($file);
}
function forceDirectory($dir){ // force directory structure
return is_dir($dir) or (acmeCache::forceDirectory(dirname($dir)) and mkdir($dir, 0777));
}
}
function repHtml($data){
//$pattern = "|·<a href=(.*) target=_blank>(.*)</a>|Us"; //表格内的行
$pattern = "|<a href=\"http://(.*)\"|Us"; //表格内的行
//  preg_match_all($pattern,$data,$matches);
//
$data=preg_replace($pattern, '<a href="ad.php?p=$1"',$data);
//  foreach($matches[1] as $key =>$value)
//{
////echo $value."\n";
//}
return $data;
}
$cache_active = true;
$cache_folder = 'cache/';
$key="zhuanti/share/intr.shtml";
$result = acmeCache::fetch($key, 300+rand()%1); // 2-4分钟
{
$data = file_get_contents ("http://www.jinghua.cn/zhuanti/share/intr.shtml");
$result =  repHtml($data);
acmeCache::save($key, $result);
}
echo $result;

?>