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【正则】为何这写也有效呢

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Release： 2016-06-13 12:59:47
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【正则】为什么这写也有效呢？

本帖最后由 php441914320 于 2012-12-10 12:28:48 编辑 匹配压缩包文件名(x.rar x.rar x.7z)：

我是这么写的：
'/^\w+\.rar$|^\w+\.zip$|^\w+\.7z$/i'
Copy after login

但是后来发现这么写也可以：
'/^\w+\.rar|zip|7z$/i'
Copy after login


关于“|”这个符号的理解还是不到位啊，求指教。

关于第二个正则表达式，按我的理解应该这样执行：
比如我有已经压缩包名为“test.rar”
第一个匹配：“test.rar”匹配是失败的。
第二次匹配：应该匹配“zip”但为什么匹配了“^\w+\.zip$”？


------解决方案--------------------
最好读一下文件的头信息，服务器端验一下文件的真实性~
引用:
引用:推荐一个函数， pathinfo();
PHP code?1/^\w+\.(rar
------解决方案--------------------
zip
------解决方案--------------------
7z)$/i
这么写就没问题了，o(∩_∩)o 哈哈。
Related labels：
nbsp rar test zip
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