javascript - 顶级域的电子邮件地址验证

Question

我们的 QA 提交了一个错误，指出电子邮件地址的顶级域不能是一个字符。

foo@bar.z

我很难研究标准。有人可以确认设置顶级域最小长度是否正确吗？

Answer 1

The rules for validating email addresses are as complicated as they are likely to be buggy in their implementation.

Rather than validating an email address, consider verifying it directly instead: http://davidcel.is/blog/2012/09/06/stop-validating-email-addresses-with-regex/

The problem with your case, is that there is a very real possibility that ICANN might introduce single-letter top-level domain names, and individual DNS labels can be of length 1, in fact "bar.z" is a valid email address domain name if sent from within a DNS tree/organization where that exists as a sub-domain (i.e. if the mailserver is smtp.mycompany.org and I've also defined an MX server for bar.z.mycompany.org).

Answer 2

请注意，我为此编写了一个名为libtld的小型 C 库。它可能对你有用。请注意，支持全球所有 TLD 所需的数据量非常惊人，因此我不会在 Javascript 中实现此类。话虽如此，也许如果您可以更多地压缩数据...该库还包括一个 PHP 扩展，因此您可以直接使用 PHP 的函数和结果。

Answer 3

到目前为止，电子邮件顶级域的长度应该在[2,6]，但它不是一个恒定的标准，因为一切都在变化。验证电子邮件非常困难，在您尝试向其发送电子邮件之前，您无法知道一个电子邮件地址是否真的可以接收电子邮件，尽管它符合电子邮件的正式标准。