php获取用户当前所使用浏览器和操作系统

<?php
function brower(){
$brower = $_SERVER['HTTP_USER_AGENT'];
if(preg_match('/360SE/', $brower)){
$brower = "360se";
}
elseif (preg_match('/Maxthon/', $brower)){
$brower = "Maxthon";
}
elseif (preg_match('/Tencent/', $brower)){
$brower = "Tencent Brower";
}
elseif (preg_match('/Green/', $brower)){
$brower = "Green Brower";
}
elseif (preg_match('/baidu/', $brower)){
$brower = "baidu";
}
elseif (preg_match('/TheWorld/', $brower)){
$brower = "The World";
}
elseif (preg_match('/MetaSr/', $brower)){
$brower = "Sogou Brower";
}
elseif (preg_match('/Firefox/', $brower)){
$brower = "Firefox";
}
elseif (preg_match('/MSIE\s6\.0/', $brower)){
$brower = "IE6.0";
}
elseif (preg_match('/MSIE\s7\.0/', $brower)){
$brower = "IE7.0";
}
elseif (preg_match('/MSIE\s8\.0/', $brower)){
$brower = "IE8.0";
}
elseif (preg_match('/MSIE\s9\.0/', $brower)){
$brower = "IE9.0";
}
elseif (preg_match('/Netscape/', $brower)){
$brower = "Netscape";
}
elseif (preg_match('/Opera/', $brower)){
$brower = "Opera";
}
elseif (preg_match('/Chrome/', $brower)){
$brower = "Chrome";
}
elseif (preg_match('/Gecko/', $brower)){
$brower = "Gecko";
}
elseif (preg_match('/Safari/', $brower)){
$brower = "Safari";
}
else{
$brower = "Unknow browser";
}
return $brower;
}
function os(){
$os = $_SERVER['HTTP_USER_AGENT'];
if(preg_match('/NT\s5\.1/', $os)){
$os = "Windows XP";
}
elseif (preg_match('/NT\s6\.0/', $os)){
$os = 'Windows Vista \ server 2008';
}
elseif (preg_match('/NT\s5\.2/', $os)){
$os = "Windows Server 2003";
}
elseif (preg_match('/NT\s5/', $os)){
$os = "Windows 2000";
}
elseif (preg_match('/NT/', $os)){
$os = "Windows NT";
}
elseif (preg_match('/NT\s6\.1/', $os)){
$os = "Windows 7";
}
elseif (preg_match('/Linux/', $os)){
$os = "Linux";
}
elseif (preg_match('/Unix/', $os)){
$os = "Unix";
}
elseif (preg_match('/Mac/', $os)){
$os = "Macintosh";
}
elseif (preg_match('/NT\s6\.1/', $os)){
$os = "Windows 7";
}
else{
$os = "Unknow OS";
}
return $os;
}

echo '此用户当前使用的浏览器：'.brower();
echo '<br />';
echo '此用户当前电脑操作系统：'.os();
?>