(转)PHP自动识别字符集并完成转码

     function safeEncoding($string,$outEncoding ='UTF-8')   
    {   
        $encoding = "UTF-8";   
       for($i=0;$i<strlen($string);$i++)   
        {   
             if(ord($string{$i})<128)   
                 continue;   
       
            if((ord($string{$i})&224)==224)   
             {   
              //第一个字节判断通过   
               $char = $string{++$i};   
                if((ord($char)&128)==128)   
               {   
                    //第二个字节判断通过   
                    $char = $string{++$i};   
                    if((ord($char)&128)==128)   
                    {   
                        $encoding = "UTF-8";   
                      break;   
                   }   
                }   
           }   
           if((ord($string{$i})&192)==192)   
            {   
                //第一个字节判断通过   
               $char = $string{++$i};   
                if((ord($char)&128)==128)   
                {   
                    // 第二个字节判断通过   
                    $encoding = "GB2312";   
                     break;   
                 }   
            }   
         }   
            
         if(strtoupper($encoding) == strtoupper($outEncoding))   
             return $string;   
         else  
             return iconv($encoding,$outEncoding,$string);   
   }