php HTTP_USER_AGENT 如何工作？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/13252603/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How does HTTP_USER_AGENT work?
提问by botenvouwer
Possible Duplicate:
Why navigator.appCodeName returning Mozilla?
When I get the PHP server variable HTTP_USER_AGENTwith this code:
当我HTTP_USER_AGENT使用此代码获取 PHP 服务器变量时：
<?php
$useragent = $_SERVER ['HTTP_USER_AGENT'];
echo "<b>Your User Agent is</b>: " . $useragent;
?>
I get this in Google chrome:
我在谷歌浏览器中得到了这个：
Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.4 (KHTML, like Gecko) Chrome/22.0.1229.94 Safari/537.4
Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.4 (KHTML, like Gecko) Chrome/22.0.1229.94 Safari/537.4
This in firefox:
这在火狐：
Mozilla/5.0 (Windows NT 6.1; rv:16.0) Gecko/20100101 Firefox/16.0
Mozilla/5.0 (Windows NT 6.1; rv:16.0) Gecko/20100101 Firefox/16.0
And this in IE:
这在 IE 中：
Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; BOIE9;NLNL)
Mozilla/5.0（兼容；MSIE 9.0；Windows NT 6.1；Trident/5.0；BOIE9；NLNL）
My obvious question is how does this work. Why does my user-agent say Mozilla and Windows NT while I am using Google chrome?
我的明显问题是这是如何工作的。当我使用 Google chrome 时，为什么我的用户代理会说 Mozilla 和 Windows NT？
Also why does it say that I use firefox when I am using IE?
另外为什么它说我在使用IE时使用firefox？
回答by Roy Dictus
The user agent string is a text that the browsers themselves send to the webserver to identify themselves, so that websites can send different content based on the browser or based on browser compatibility.
用户代理字符串是浏览器自己发送给网络服务器以标识自己的文本，以便网站可以根据浏览器或浏览器兼容性发送不同的内容。
Mozilla is a browser rendering engine (the one at the core of Firefox) and the fact that Chrome and IE contain the string Mozilla/4 or /5 identifies them as being compatible with that rendering engine.
Mozilla 是一种浏览器渲染引擎（Firefox 的核心引擎），Chrome 和 IE 包含字符串 Mozilla/4 或 /5 的事实表明它们与该渲染引擎兼容。
回答by Prash
http://www.useragentstring.com/
http://www.useragentstring.com/
Visit that page, it'll give you a good explanation of each element of your user agent.
访问那个页面，它会给你一个很好的解释你的用户代理的每个元素。
Mozilla:
移动版：
MozillaProductSlice. Claims to be a Mozilla based user agent, which is only true for Gecko browsers like Firefox and Netscape. For all other user agents it means 'Mozilla-compatible'. In modern browsers, this is only used for historical reasons. It has no real meaning anymore
Mozilla 产品切片。声称是基于 Mozilla 的用户代理，这仅适用于 Firefox 和 Netscape 等 Gecko 浏览器。对于所有其他用户代理，它意味着“与 Mozilla 兼容”。在现代浏览器中，这仅用于历史原因。它已经没有真正的意义了
