正则表达式 – 你看到的最长的正则表达式是什么？

用于验证电子邮件地址的正则表达式(可能多个到:,cc：和bcc：form)(从 RFC 822)是非常强大的;绝对是我看到的最长的非平凡的正则表达式。不幸的是，似乎有很多网站在互联网上没有使用这个正则表达式或等效的验证，因为我遇到太多的网站不接受myemailaddress yourstupidsite@gmail.com作为一个有效的电子邮件地址。

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