REGEX Email Validation To Not Allow Commas In Domains

Question

I am using the following expression to validate emails:

^[a-zA-Z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-zA-Z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-zA-Z0-9](?:[a-zA-Z0-9-]*[a-zA-Z0-9])?\.)+(?:[a-zA-Z]{2}|com|COM|CoM|cOM|coM|COm|edu|org|net|gov|biz|info|name|aero|biz|info|jobs|museum)\b

However, it still allows me to enter an invalid email such as below...

mynameis@domain.co,uk

I want to not allow the comma between the co and uk.

Any suggestions?

Regex can be quite different across different languages. Which language you're using? — vandershraaf, Jun 27 '12 at 15:55
You don't seem to allow commas anywhere, is that what you are after? — BlackVegetable, Jun 27 '12 at 15:55
Did you search SO for email validation regex? This question has been asked many times before. — Jonathan M, Jun 27 '12 at 15:56
maybe you need to escape some special characters (like +) to improve your regex — Hachi, Jun 27 '12 at 15:56
http://stackoverflow.com/questions/201323/how-to-use-a-regular-expression-to-validate-an-email-addresses — mihaisimi, Jun 27 '12 at 15:56
sometimes the best way is to split e-mail by `'@'` and check first and second parts of splitted string. — gaussblurinc, Jun 28 '12 at 14:29

BlackVegetable · Answer 1 · 2014-04-01T14:23:19.653

3

If you do not want commas anywhere, you could try to lookahead. ^(.(?!,))*$ With this, if you have a comma anywhere, it will no longer match. Of course you'll need to place this in your existing expression, without the start and end anchors. I recommend Regexpal to test such regular expressions.

Additionally, you may wish to exclude double periods from your email address. I use:

^(?!.*\.{2})[ ]*[\w]+[\w\.]*[\w]*@[\w]+\.[a-zA-Z]+[ ]* for my needs.

Now \w allows for [A-Za-z0-9_] which is odd due to the underscore but I'm pretty sure underscores are allowed in email addresses. This also prevents a double period in your email address as well as not allowing the first or last character to be a period, which is illegal.

edited Apr 01 '14 at 14:23

answered Jun 27 '12 at 16:02

BlackVegetable

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Yes, I don't want to allow commas anywhere as this is only for a single email address, so no need to add a comma separator for multiple email addresses. – Steve Jun 28 '12 at 08:22
This one seems to work... ^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$ – Steve Jun 28 '12 at 09:53
That might work, however be careful as you cannot have two consecutive periods in a row with your email address. I'll update my answer with a solution for that. – BlackVegetable Jun 28 '12 at 14:05

REGEX Email Validation To Not Allow Commas In Domains

1 Answers1