力圖打造一個完美的方法來檢查電子郵件是否有效是沒有意義的。這是檢查電子郵件地址是否有效的正則表達式according to RFC822。
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這完全是矯枉過正。在「普通」代碼中執行此操作也會很長時間。您無需驗證完美的電子郵件地址。您也不需要擔心速度/效率。這被稱爲過早優化,你不應該這樣做。當你應該在自己的應用程序/項目上工作時,你只是在浪費你的時間。
這裏有一個很好的正則表達式,你可以使用
\b[A-Z0-9._%+-][email protected][A-Z0-9.-]+\.[A-Z]{2,4}\b
這裏有一個更好的將匹配的電子郵件
[\w!#$%&'*+/=?^`{|}~-]+(?:\.[\w!#$%&'*+/=?^`{|}~-]+)*@(?:\w(?:[\w-]*\w)?\.)+\w(?:[\w-]*\w)?
正則表達式是在側的疼痛,這是真的,但幸運的是成千上萬的程序員,你已經越過這條道路,並已經[生產的高效,準確的電子郵件正則表達式]之前(HTTP://www.regular- expressions.info/regexbuddy/email.html)。長期保存一段時間,學習正則表達式。 – Neil 2012-04-18 14:49:59
@Neil - 該正則表達式不再準確。現在頂級域名的長度可以超過4個字符(例如mydomain.museum)和電子郵件地址可以包含Unicode字符,如δοκιμή@παράδειγμα.δοκιμή,以及任何#$的%&'* + -/=?^_' {|}〜。 – 2012-04-18 15:16:01