PHP加密解密也是常有的事，发现discuz论坛里的PHP加密解密处理类代码，感觉挺不错，在用的时候，要参考Discuz论坛的passport相关函数，后面我会附上使用方法。

php加密解密处理类<?php

/*========================================================

= 文件名称：cls.sys_crypt.php

= 摘 要：php加密解密处理类 www.qdxw.net

= 参 考：Discuz论坛的passport相关函数

=========================================================*/

class SysCrypt {

private $crypt_key;

// 构造函数

public function __construct($crypt_key) {

$this -> crypt_key = $crypt_key;

}

public function php_encrypt($txt) {

srand((double)microtime() * 1000000);

$encrypt_key = md5(rand(0,32000));

$ctr = 0;

$tmp = '';

for($i = 0;$i

$ctr = $ctr == strlen($encrypt_key) ? 0 : $ctr;

$tmp .= $encrypt_key[$ctr].($txt[$i]^$encrypt_key[$ctr++]);

}

return base64_encode(self::__key($tmp,$this -> crypt_key));

}

public function php_decrypt($txt) {

$txt = self::__key(base64_decode($txt),$this -> crypt_key);

$tmp = '';

for($i = 0;$i < strlen($txt); $i++) {

$md5 = $txt[$i];

$tmp .= $txt[++$i] ^ $md5;

}

return $tmp;

}

private function __key($txt,$encrypt_key) {

$encrypt_key = md5($encrypt_key);

$ctr = 0;

$tmp = '';

for($i = 0; $i < strlen($txt); $i++) {

$ctr = $ctr == strlen($encrypt_key) ? 0 : $ctr;

$tmp .= $txt[$i] ^ $encrypt_key[$ctr++];

}

return $tmp;

}

public function __destruct() {

$this -> crypt_key = null;

}

}

?>

使用方法说明<?php

//使用前请先引入类文件，如：

include 'cls.sys_crypt.php';

$sc = new SysCrypt('phpwms');

$text = '110';

print($sc -> php_encrypt($text));

print('
');

print($sc -> php_decrypt($sc -> php_encrypt($text)));

?>