PHP gets browser version and operating system version

$user_agent = $_SERVER['HTTP_USER_AGENT']; // 先取得UA  
// echo $user_agent;  
  
const REG_ALL = '/(Opera|OPR|Firefox|Chrome|Safari|MSIE|Navigator).(\d{1,3}\.\d{0,2})/i'; // 此处可以加入想要捕获的浏览器标识  
  
preg_match(REG_ALL, $user_agent, $matches); // 这里查下PHP文档  
  
/** 大致返回结果像这样 
array (size=3) 
    0 => string 'Firefox/39.0' (length=12) 
    1 => string 'Firefox' (length=7) 
    2 => string '39.0' (length=4) 
 */  
  
const REG_OS = '/(Windows NT|Win |Linux|Unix|Sun|Mac).(\d{1,3}\.\d{0,2})/i'; // 这里仅做了测试项目  
  
preg_match(REG_OS, $user_agent, $matches); // 操作系统如是乎  
  
/* 返回值类似这样似的，自己再做解析，6.1:Win7 5.1:XP 什么的 
array (size=3) 
  0 => string 'Windows NT 6.1' (length=14) 
  1 => string 'Windows NT' (length=10) 
  2 => string '6.1' (length=3) 
*/  
die();