力图打造一个完美的方法来检查电子邮件是否有效是没有意义的。这是检查电子邮件地址是否有效的正则表达式according to RFC822。
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+|\Z|(?=[\["()<>@,;:\\".\[\]]))|\[([^\[\]\r\\]|\\.)*\](?:(?:\r\n)?[ \t])*)(?:\
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这完全是矫枉过正。在“普通”代码中执行此操作也会很长时间。您无需验证完美的电子邮件地址。您也不需要担心速度/效率。这被称为过早优化,你不应该这样做。当你应该在自己的应用程序/项目上工作时,你只是在浪费你的时间。
这里有一个很好的正则表达式,你可以使用
\b[A-Z0-9._%+-][email protected][A-Z0-9.-]+\.[A-Z]{2,4}\b
这里有一个更好的将匹配的电子邮件
[\w!#$%&'*+/=?^`{|}~-]+(?:\.[\w!#$%&'*+/=?^`{|}~-]+)*@(?:\w(?:[\w-]*\w)?\.)+\w(?:[\w-]*\w)?
正则表达式是在侧的疼痛,这是真的,但幸运的是成千上万的程序员,你已经越过这条道路,并已经[生产的高效,准确的电子邮件正则表达式]之前(HTTP://www.regular- expressions.info/regexbuddy/email.html)。长期保存一段时间,学习正则表达式。 – Neil 2012-04-18 14:49:59
@Neil - 该正则表达式不再准确。现在顶级域名的长度可以超过4个字符(例如mydomain.museum)和电子邮件地址可以包含Unicode字符,如δοκιμή@παράδειγμα.δοκιμή,以及任何#$的%&'* + -/=?^_' {|}〜。 – 2012-04-18 15:16:01