Completely off topic.

Is anybody on here a guru with RegEx (regular expressions)?

I'm having trouble with the one that validates the format of an email address (for the login on this web site). And I can't get my head around fixing the issue.

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We use the following - written by a colleague, so can't comment on any false positives etc.

^[^@ ]+@[^.@ ]+(\.[^.@ ]+)+$

Robin

Thank you 🙂 I'm using:

^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$"

Which seems inordinately long in comparison. But so far I've had two complaints:

1, It didn't let through a + symbol in an email address prefix (you know who you are!)

2, It didn't let through a CompuServe email address in the format [email protected]

Looking at your example it looks as if it would pass those two. I'll give it a go...

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That seems to work very nicely. Thank you. :flowers:

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^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$"

:blink:

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^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$"

:blink:

Is that a new mine somewhere? :confused::confused::confused:

Let me guess, pot noodle?

We use the following - written by a colleague, so can't comment on any false positives etc.

^[^@ ]+@[^.@ ]+(\.[^.@ ]+)+$

&@!.* seems to be an acceptable address according to the above (or am I misreading it?).
Should the conditions for the domain name be tighter?

We use the following - written by a colleague, so can't comment on any false positives etc.

^[^@ ]+@[^.@ ]+(\.[^.@ ]+)+$

&@!.* seems to be an acceptable address according to the above (or am I misreading it?).
Should the conditions for the domain name be tighter?

You're correct, it does let that through 😢

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My brain hurts. :surrender:

Looks like the sort of thing characters in the Beano used to say when they dropped anvils on their foot.

We use the following - written by a colleague, so can't comment on any false positives etc.

^[^@ ]+@[^.@ ]+(\.[^.@ ]+)+$

&@!.* seems to be an acceptable address according to the above (or am I misreading it?).
Should the conditions for the domain name be tighter?

It's complicated ... :(

See RFC 5321 and RFC 5322, and extensions like RFC 6531 etc. for more than you really want to know about email addresses. :confused:

The simple case is that domain names should (generally) contain only the ASCII letters 'a' to 'z' (in a case-insensitive manner), the digits '0' to '9', and the hyphen ('-'), so in the example that skimble gives, the domain name !.* is not valid. (This simple specification does not allow for non-ASCII characters in domain names or non-latin scripts, both of which are permissible). Also, there are length limitations on the domain names parts and the overall length.

A more strict regex might be:

^[^@ ]+@[0-9A-Za-Z\-]{1,62}(\.[0-9A-Za-Z\-]{1,62})+$

In addition, the hostname (including dots) should not be more than 254 characters.

However, the above regex does not validate internationalized domain names such as üñîçøðé@üñîçøðé.com, literal IPv6 addresses such as user@[IPv6:2001:db8::1] or those in non-latin scripts (I leave those as an exercise for the reader 🙂 )

Dave

One should, of course, remember that the reverse diagonal should be avoided unless preceded by a 3-character cyclical. Failure to observe this simple rule brings Moreton’s convention into play and there's no knowing where you'll end up!

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One should, of course, remember that the reverse diagonal should be avoided unless preceded by a 3-character cyclical. Failure to observe this simple rule brings Moreton’s convention into play and there's no knowing where you'll end up!

Mornington Crescent!

Mornington Crescent!

Blimey, that was quick! :thumbsup:

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My brain hurts. :surrender:

Mine too --- AAARGH---:o:o

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Mine too

Repetition! - oops, wrong game.

^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$"

:blink:

Is that a new mine somewhere? :confused::confused::confused:

Let me guess, pot noodle?

Actually its the Midnight Oil Well.

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if you come over from the dark side I've a few neat php routines I've put together over the years that are pretty robust for fishing through strings in an email address

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if you come over from the dark side I've a few neat php routines I've put together over the years that are pretty robust for fishing through strings in an email address

Recoding the entire site in PHP would be a bit of an undertaking :lol:

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