PHP学习：php实现获取及设置用户访问页面语言类

<?php 
/** User Language Class 获取/设置用户拜访的页面语言,如果用户没有设置拜访语言,则读取Accept-Language 
*  Date:  2014-05-26 
*  Author: fdipzone 
*  Ver:  1.0 
* 
*  Func: 
*  public get        获取用户拜访语言 
*  public set        设置用户拜访语言 
*  private getAcceptLanguage 获取HTTP_ACCEPT_LANGUAGE 
*/ 
 
class UserLang{ // class start 
 
  private $name = 'userlang'; // cookie name 
  private $expire = 2592000; // cookie expire 30 days 
 
 
  /** 初始化 
  * @param String $name  cookie name 
  * @param int  $expire cookie expire 
  */ 
  public function __construct($name='', $expire=null){ 
 
    // 设置cookie name 
    if($name!=''){ 
      $this->name = $name; 
    } 
 
    // 设置cookie expire 
    if(is_numeric($expire) && $expire>0){ 
      $this->expire = intval($expire); 
    } 
  } 
 
  /** 获取用户拜访语言 */ 
  public function get(){ 
 
    // 判断用户是否有设置过语言 
    if(isset($_COOKIE[$this->name])){ 
      $lang = $_COOKIE[$this->name]; 
    }else{ 
      $lang = $this->getAcceptLanguage(); 
    } 
    return $lang; 
  } 
 
  /** 设置用户拜访语言 
  * @param String $lang 用户拜访语言 
  */ 
  public function set($lang=''){ 
 
    $lang = strtolower($lang); 
 
    // 只能是英文,简体中文,繁体中文 
    if(in_array($lang, array('en','sc','tc'))){ 
      setcookie($this->name, $lang, time()+$this->expire); 
    } 
  } 
 
 
  /** 获取HTTP_ACCEPT_LANGUAGE */ 
  private function getAcceptLanguage(){ 
 
    $lang = strtolower($_SERVER['HTTP_ACCEPT_LANGUAGE']); 
 
    if(in_array(substr($lang,0,5), array('zh-tw','zh_hk'))){ 
      $lang = 'tc'; 
    }elseif(in_array(substr($lang,0,5), array('zh-cn','zh-sg'))){ 
      $lang = 'sc'; 
    }else{ 
      $lang = 'en'; 
    } 
 
    return $lang; 
  } 
} // class end 
?> 

<?php 
 
require "UserLang.class.php"; 
 
$obj = new UserLang('sitelang', 3600); 
echo $obj->get().'<br>'; 
?>