php正则表达式替换URL链接地址为指定url

<?php
$str = "The quick brown fox jumped over the lazy dog.";
$str = preg_replace('/s/','-',$str);
echo $str;
?>
输出结果为：

The-quick-brown-fox-jumped-over-the-lazy-dog.

<?php
$str = "The quick brown fox jumped over the lazy dog.";

$patterns[0] = "/quick/";
$patterns[1] = "/brown/";
$patterns[2] = "/fox/";

$replacements[2] = "bear";
$replacements[1] = "black";
$replacements[0] = "slow";

print preg_replace($patterns, $replacements, $str);
/*输出：
The bear black slow jumped over the lazy dog.
*/
ksort($replacements);
print preg_replace($patterns, $replacements, $str);
/*输出：
The slow black bear jumped over the lazy dog.
*/
?>

<?php
$a = '<a href="http://bootstrap.jincon.com/" target="_blank">Bootstrap中文网</a>提供<a href="http://bootstrap.jincon.com/" target="_blank">Bootstrap中文手册</a>，学习<a href="http://bootstrap.jincon.com/" target="_blank">Bootstrap入门教程</a>，<a href="http://bootstrap.jincon.com/" target="_blank">Bootstrap</a>是Twitter推出的一个用于前端开发的开源工具包。它由Twitter的设计师Mark Otto和Jacob Thornton合作开发，是一个CSS/HTML框架。<a href="http://bootstrap.jincon.com/" target="_blank">Bootstrap中文网</a>致力于为广大国内开发者提供详尽的中文文档、代码实例等，助力开发者掌握并使用这一框架。';

$lines_string=preg_replace("(<a[^>]*>(.+?)</a>)","<a href='http://www.yifen5.com/tag/$1'>$1</a>",$a);
print_r($lines_string);
?>

/**
* Memcached的过期内存回收
*/
class mem_dtor extends Memcache
{
private $server_id;
public function __construct($host,$port)
{
$this->server_id = "$host:$port";
$this->connect($host,$port);
}

// 回收所有过期的内存
public function gc()
{
$t = time();
$_this = $this;
$func = function($key,$info) use ($t,$_this)
{
if($info[1] - $t delete($key);
}
};
$this->lists($func);
}

// 查看所有缓存内容的信息
public function info()
{
$t = time();
$func = function($key,$info) use ($t)
{
echo $key,' => Exp:',$info[1] - $t,"n"; //查看缓存对象的剩余过期时间
};
$this->lists($func);
}

private function lists($func)
{
$sid = $this->server_id;
$items = $this->getExtendedStats('items'); //获取memcached状态
foreach($items[$sid]['items'] as $slab_id => $slab) //获取指定server id 的 所有Slab
{
$item = $this->getExtendedStats('cachedump',$slab_id,0); //遍历所有Slab
foreach($item[$sid] as $key => $info) //获取Slab中缓存对象信息
{
$func($key,$info);
}
}
}
}

$mem = new mem_dtor('127.0.0.1',11211);
$mem->info();//查看状态
$mem->gc(); //回收

<?
function PMA_getenv($var_name) {
if (isset($_SERVER[$var_name])) {
return $_SERVER[$var_name];
} elseif (isset($_ENV[$var_name])) {
return $_ENV[$var_name];
} elseif (getenv($var_name)) {
return getenv($var_name);
} elseif (function_exists('apache_getenv')
&& apache_getenv($var_name, true)) {
return apache_getenv($var_name, true);
}
return '';
}
if (empty($HTTP_HOST)) {
if (PMA_getenv('HTTP_HOST')) {
$HTTP_HOST = PMA_getenv('HTTP_HOST');
} else {
$HTTP_HOST = '';
}
}
echo htmlspecialchars($HTTP_HOST);
?>

<?php
function GetIP() {
    if (isset($_SERVER["HTTP_X_FORWARDED_FOR"]))
        $ip = $_SERVER["HTTP_X_FORWARDED_FOR"];
    else if (isset($_SERVER["HTTP_CLIENT_IP"]))
        $ip = $_SERVER["HTTP_CLIENT_IP"];
    else if (isset($_SERVER["REMOTE_ADDR"]))
        $ip = $_SERVER["REMOTE_ADDR"];
    else if (getenv("HTTP_X_FORWARDED_FOR"))
        $ip = getenv("HTTP_X_FORWARDED_FOR");
    else if (getenv("HTTP_CLIENT_IP"))
        $ip = getenv("HTTP_CLIENT_IP");
    else if (getenv("REMOTE_ADDR"))
        $ip = getenv("REMOTE_ADDR");
    else
        $ip = "Unknown";
    return $ip;
}
echo GetIP();
?>

<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<?php
/******************************************************************************

参数说明:
$max_file_size  : 上传文件大小限制, 单位BYTE
$destination_folder : 上传文件路径
$watermark   : 是否附加水印(1为加水印,其他为不加水印);

使用说明:
. 将PHP.INI文件里面的"extension=php_gd2.dll"一行前面的;号去掉,因为我们要用到GD库;
. 将extension_dir =改为你的php_gd2.dll所在目录;
******************************************************************************/

//上传文件类型列表
$uptypes=array(
    'image/jpg',
    'image/jpeg',
    'image/png',
    'image/pjpeg',
    'image/gif',
    'image/bmp',
    'image/x-png'
);

$max_file_size=2000000;     //上传文件大小限制, 单位BYTE
$destination_folder="uploadimg/"; //上传文件路径
$watermark=1;      //是否附加水印(1为加水印,其他为不加水印);
$watertype=1;      //水印类型(1为文字,2为图片)
$waterposition=1;     //水印位置(1为左下角,2为右下角,3为左上角,4为右上角,5为居中);
$waterstring="http://www.xplore.cn/";  //水印字符串
$waterimg="xplore.gif";    //水印图片
$imgpreview=1;      //是否生成预览图(1为生成,其他为不生成);
$imgpreviewsize=1/2;    //缩略图比例
?>
<html>
<head>
<title>ZwelL图片上传程序</title>
<style type="text/css">
<!--
body
{
     font-size: 9pt;
}
input
{
     background-color: #66CCFF;
     border: 1px inset #CCCCCC;
}
-->
</style>
</head>

<body>
<form enctype="multipart/form-data" method="post" name="upform">
  上传文件:
  <input name="upfile" type="file">
  <input type="submit" value="上传"><br>
  允许上传的文件类型为:<?=implode(', ',$uptypes)?>
</form>

<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST')
{
    if (!is_uploaded_file($_FILES["upfile"][tmp_name]))
    //是否存在文件
    {
         echo "图片不存在!";
         exit;
    }

    $file = $_FILES["upfile"];
    if($max_file_size < $file["size"])
    //检查文件大小
    {
        echo "文件太大!";
        exit;
    }

    if(!in_array($file["type"], $uptypes))
    //检查文件类型
    {
        echo "文件类型不符!".$file["type"];
        exit;
    }

    if(!file_exists($destination_folder))
    {
        mkdir($destination_folder);
    }

    $filename=$file["tmp_name"];
    $image_size = getimagesize($filename);
    $pinfo=pathinfo($file["name"]);
    $ftype=$pinfo['extension'];
    $destination = $destination_folder.time().".".$ftype;
    if (file_exists($destination) && $overwrite != true)
    {
        echo "同名文件已经存在了";
        exit;
    }

    if(!move_uploaded_file ($filename, $destination))
    {
        echo "移动文件出错";
        exit;
    }

    $pinfo=pathinfo($destination);
    $fname=$pinfo[basename];
    echo " <font color=red>已经成功上传</font><br>文件名:  <font color=blue>".$destination_folder.$fname."</font><br>";
    echo " 宽度:".$image_size[0];
    echo " 长度:".$image_size[1];
    echo "<br> 大小:".$file["size"]." bytes";

    if($watermark==1)
    {
        $iinfo=getimagesize($destination,$iinfo);
        $nimage=imagecreatetruecolor($image_size[0],$image_size[1]);
        $white=imagecolorallocate($nimage,255,255,255);
        $black=imagecolorallocate($nimage,0,0,0);
        $red=imagecolorallocate($nimage,255,0,0);
        imagefill($nimage,0,0,$white);
        switch ($iinfo[2])
        {
            case 1:
            $simage =imagecreatefromgif($destination);
            break;
            case 2:
            $simage =imagecreatefromjpeg($destination);
            break;
            case 3:
            $simage =imagecreatefrompng($destination);
            break;
            case 6:
            $simage =imagecreatefromwbmp($destination);
            break;
            default:
            die("不支持的文件类型");
            exit;
        }

        imagecopy($nimage,$simage,0,0,0,0,$image_size[0],$image_size[1]);
        imagefilledrectangle($nimage,1,$image_size[1]-15,80,$image_size[1],$white);

        switch($watertype)
        {
            case 1:   //加水印字符串
            imagestring($nimage,2,3,$image_size[1]-15,$waterstring,$black);
            break;
            case 2:   //加水印图片
            $simage1 =imagecreatefromgif("xplore.gif");
            imagecopy($nimage,$simage1,0,0,0,0,85,15);
            imagedestroy($simage1);
            break;
        }

        switch ($iinfo[2])
        {
            case 1:
            //imagegif($nimage, $destination);
            imagejpeg($nimage, $destination);
            break;
            case 2:
            imagejpeg($nimage, $destination);
            break;
            case 3:
            imagepng($nimage, $destination);
            break;
            case 6:
            imagewbmp($nimage, $destination);
            //imagejpeg($nimage, $destination);
            break;
        }

        //覆盖原上传文件
        imagedestroy($nimage);
        imagedestroy($simage);
    }

    if($imgpreview==1)
    {
    echo "<br>图片预览:<br>";
    echo "<img src="".$destination."" width=".($image_size[0]*$imgpreviewsize)." height=".($image_size[1]*$imgpreviewsize);
    echo " alt="图片预览:r文件名:".$destination."r上传时间:">";
    }
}
?>
</body>
</html>