I have done some testing but I wanted to ask if anyone sees a problem with this ruby regular expression for email validation:
/\A([^@\s]+)@((?:[-a-z0-9]+.)+[a-z]{2,})\Z/i
Look good?
Thanks,
Tony
I have done some testing but I wanted to ask if anyone sees a problem with this ruby regular expression for email validation:
/\A([^@\s]+)@((?:[-a-z0-9]+.)+[a-z]{2,})\Z/i
Look good?
Thanks,
Tony
You were close, have to add just a few more characters:
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No, I'm not joking: http://www.ex-parrot.com/~pdw/Mail-RFC822-Address.html
One valid character that people always miss is the '%' character. It performs an internal routing direction. See email addresses section 17.3.3.
Note that this is regarded as legacy. However it shows that you're looking to do something quite complicated. I'd perhaps just check for a @ character and a suitable-looking domain suffix.
EDIT: I forgot. You can now get Unicode domain names e.g. http://☃.net/ (Stackoverflow's HTML editor gets a bit mixed up by this)
Have a look at the following links.
Comparing E-mail Address Validating Regular Expressions
How to Find or Validate an Email Address
There is also a similar question at stack overflow.
Validating e-mail addresses tends to be more complicated than you'd think.
/^(?!(?>\x22?(?>\x5C[\x00-\x7E]|[^\x22\x5C])\x22?){255,})(?!(?>\x22?(?>\x5C[\x00-\x7E]|[^\x22\x5C])\x22?){65,}@)(?>[\x21\x23-\x27\x2A\x2B\x2D\x2F-\x39\x3D\x3F\x5E-\x7E]+|(?>\x22(?>[\x01-\x08\x0B\x0C\x0E-\x1F\x21\x23-\x5B\x5D-\x7F]|\x5C[\x00-\x7F])*\x22))(?>\.(?>[\x21\x23-\x27\x2A\x2B\x2D\x2F-\x39\x3D\x3F\x5E-\x7E]+|(?>\x22(?>[\x01-\x08\x0B\x0C\x0E-\x1F\x21\x23-\x5B\x5D-\x7F]|\x5C[\x00-\x7F])*\x22)))*@(?>(?>(?!.*[^.]{64,})(?>(?>xn--)?[a-z0-9]+(?>-[a-z0-9]+)*\.){0,126}(?>xn--)?[a-z0-9]+(?>-[a-z0-9]+)*)|(?:\[(?>(?>IPv6:(?>(?>[a-f0-9]{1,4}(?>:[a-f0-9]{1,4}){7})|(?>(?!(?:.*[a-f0-9][:\]]){8,})(?>[a-f0-9]{1,4}(?>:[a-f0-9]{1,4}){0,6})?::(?>[a-f0-9]{1,4}(?>:[a-f0-9]{1,4}){0,6})?)))|(?>(?>IPv6:(?>(?>[a-f0-9]{1,4}(?>:[a-f0-9]{1,4}){5}:)|(?>(?!(?:.*[a-f0-9]:){6,})(?>[a-f0-9]{1,4}(?>:[a-f0-9]{1,4}){0,4})?::(?>[a-f0-9]{1,4}(?>:[a-f0-9]{1,4}){0,4}:)?)))?(?>25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])(?>\.(?>25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])){3}))\]))$/isD
Follows the RFC 5322 standard.