Regex for an email address doesn't work

Question

I\'m trying to check if some email address is correct with the following code :

NSPredicate *regexMail = [NSPredicate predicateWithFormat:@\"SELF MATCHES \'.*@.*         


        

Answer 1

You cannot correctly validate an email address with regular expressions alone. A simple search will show you many articles discussing this. The problem lies with the nature of DNS: there are too many possible domain names (including non-english and Unicode domains), you cannot correctly validate them using a regex. Don't try.

The only correct way to determine if an email address is valid is to send a message to the address with a unique URL that identifies the account associated with the email, for the user to click. Anything else will annoy your end-user.