<?php

class Guid{/** * 系统当前时间*/private static function  _curTimeMillis() {  list($usec,  $sec)  =  explode("  ",microtime());return  $sec.substr($usec,  2,  3);   }

/** * 客户端相关信息*/private static function  _getHost() {$name = empty($_SERVER["HTTP_USER_AGENT"]) ? 'localhost' : $_SERVER["HTTP_USER_AGENT"];return strtolower($name . '/' . self::_clientIp()); }

/** * 客户端IP*/private static function _clientIp() {$ip = (@$_SERVER['HTTP_REALIP']) ? $_SERVER['HTTP_REALIP'] : ((@$_SERVER['HTTP_X_FORWARDED_FOR']) ? $_SERVER['HTTP_X_FORWARDED_FOR'] : @$_SERVER['REMOTE_ADDR']);

if (empty($ip))    $ip = '0.0.0.0';return $ip; }

/** * 随机数*/private static function  _random() {$tmp  =  rand(0,1) ? '-' : '';return  $tmp.rand(1000,  9999).rand(1000,  9999).rand(1000,  9999).rand(100,  999).rand(100,  999);   }

/** * 生成GUID字符串 * (长度：32 + 4) * 三段：一段是微秒,  一段是地址,  一段是随机数*/public static function  toString() {if (function_exists('com_create_guid')) {return com_create_guid(); } else {$string = md5(self::_getHost() . ':' . self::_curTimeMillis() . ':' . self::_random());$raw  =  strtoupper($string);return  substr($raw,0,8).'-'.substr($raw,8,4).'-'.substr($raw,12,4).'-'.substr($raw,16,4).'-'.substr($raw,20); } }}

------------------------------------------------class Uuid{private $_yearCode = array('A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T');const START_YEAR = 2011;

/** * 组成结构：年份(1个字符)，月份(1个字符[十六进制])，日(2个字符)，时间戳(后5字符)，微秒(6个字符)，随机数(3个字符) ＝ 18个字符*/public static function make() {return    $this->_yearCode[intval(date('Y')) - self::START_YEAR].strtoupper(dechex(date('m'))) . date('d') .substr(time(), -5) . substr(microtime(), 2, 6) . sprintf('%02d', rand(0, 99)); }}