[RESOLVED] Need best way to remove char from Email Address

[halojoy]

Have an application with sign up and email activation.
Database will look for email and not allow more than one of each email.
I use strtolower() on the email submitted. Along with php filter validate email.

But here is my problem.
Suppose one sign up is submitted: [e-mail]
Second time same user submits: [e-mail]
The third time is submitted this: [e-mail]

The Database will not find the matching duplicate!

How can I remove all "." in john.smith
but at the same not remove the "." in yahoo.com?

I guess this is suitable for preg_match() with a regex.

[dalecosp]

"[e-mail]" is valid. "[e-mail]" is also valid. How can you be certain they are duplicated addresses?

"[e-mail]" isn't valid. Two "." in a row are not allowed, unless quoted, thus: "jo..hn.sm.ith"@yahoo.com ...

As for the original question, preg_match could be made to work as far as I know, but a simple rejection of anything with two consecutive dots should really be all that's needed?

[halojoy]

Thanks.
Gmail.com have this information:
in [e-mail] the period is ignored,
and is so the same as [e-mail]

In Stack Overflow I got the following solution to what I am trying to do:

<?php

$email = preg_replace('/\.(?=.*@)/', '', $email);

?>

It works exactly and fine. 🙂
He calls it: "look ahead"

[dalecosp]

dalecosp;11062059 wrote:

preg_match could be made to work

Of course, I meant "preg_replace" ... MySQL croaked and refused to restart after an upgrade this AM ... #brain_busy

halojoy;11062061 wrote:

Thanks.
Gmail.com have this

Ah, well, that's different then ... any email service can, of course, impose its own more restrictive rules. Are you only checking @gmail.com addresses?

<?php

$email = preg_replace('/\.(?=.*@)/', '', $email);

?>

It works exactly and fine. 🙂
He calls it: "look ahead"

Yes, it's a "positive lookahead assertion". 🙂

[halojoy]

dalecosp;11062063 wrote:

Of course, I meant "preg_replace" ... MySQL croaked and refused to restart after an upgrade this AM ... #brain_busy

Ah, well, that's different then ... any email service can, of course, impose its own more restrictive rules. Are you only checking @gmail.com addresses?

Yes, it's a "positive lookahead assertion". 🙂

dalecosp, for my sign up application with activation, I of course expect all kinds of email.
And I checked out at www.outlook.com.
Now, there is different. They so treat [e-mail] as another email than [e-mail]
So, bottomline: I must give you right.
Gmail have their rules, Outlook.com have other rules.

I have decided to not remove periods in the sign up checking.
Even if this opens up for duplicate account sign up with same Gmail.

[dalecosp]

halojoy;11062065 wrote:

Gmail have their rules, Outlook.com have other rules.

That's why we have standards ... in this case, RFC 5322. GMail is, for its own reasons, creating a more-restrictive policy than necessary.

That's not unlike Google to do, as they've decided they're the 200 pound gorilla of the Internet and they can create their own standards on the chance that they will, indeed, become standards.

I'm not so sure about this particular one though ...

I have decided to not remove periods in the sign up checking.
Even if this opens up for duplicate account sign up with same Gmail.

You could, of course, have a conditional that checks the domain portion of the address ... if it matches "gmail.com" you could do your checking, otherwise, leave it alone.

[Derokorian]

dalecosp;11062067 wrote:

That's not unlike Google to do, as they've decided they're the 200 pound gorilla of the Internet and they can create their own standards on the chance that they will, indeed, become standards.

But they aren't trying to make it standard, as only @gmail behaves this way. If you use gmail through school or an organization, dots matter.

Note: If you use Gmail through work, school, or other organization (like yourdomain.com or yourschool.edu), adding dots to your username changes your email address. To change the dots in your username, contact your admin.

So they aren't passing this behaviour off to people using the service under a different name, which is in itself kinda interesting.

[laserlight]

There's another thing about gmail email addresses though: they permit aliasing by appending "+alias" to the mailbox name, e.g., one could sign up with [e-mail] and [e-mail], hence the check should also check for this. But anyway, I agree with the decision to drop the issue: if a person wishes to sign up for multiple accounts, these may make it easier, but they can always sign up with entirely different email accounts and merely by checking the email addresses you will be none the wiser.

[dalecosp]

Derokorian;11062075 wrote:

But they aren't trying to make it standard, as only @gmail behaves this way. If you use gmail through school or an organization, dots matter.

They can't "make" it a standard; what I'm trying to say is that they lead, others follow, and then there's a chance something they do becomes a standard. I'm talking in the abstract ... I (we) don't actually know their intent with their email local-part policy, or why they chose to do it that way.

But they do have a HUGE amount of influence on the tech world and have personnel sitting in/on many standards committees/boards.

So they aren't passing this behaviour off to people using the service under a different name, which is in itself kinda interesting.

Well, they can't, because they can't guarantee that other services outside their control use the same rules for the local-part ... or am I missing something here?

[Derokorian]

dalecosp;11062081 wrote:

They can't "make" it a standard; what I'm trying to say is that they lead, others follow, and then there's a chance something they do becomes a standard. I'm talking in the abstract ... I (we) don't actually know their intent with their email local-part policy, or why they chose to do it that way.

But they do have a HUGE amount of influence on the tech world and have personnel sitting in/on many standards committees/boards.

Well, they can't, because they can't guarantee that other services outside their control use the same rules for the local-part ... or am I missing something here?

Yeah, you're missing that you can use gmail, but not be @gmail. For example, many (maybe most?) colleges use gmail, but the students have @school.edu emails, but the service is gmail. What I was saying is that even though this service is gmail, the rules are not.

Specifically [e-mail] and [e-mail] are the same, but [e-mail] and [e-mail] are not the same thing. However, I check both in gmail, I pay them for the @.com email hosting, but non-profits and schools are free. Hence the quote I included from their help site.

AKA only @gmail follows this dot rule, even though there are hundreds (thousands?) of other domains hosted by gmail.

https://gsuite.google.com/products/gmail/

[halojoy]

I found this solution.
After this my Database will not allow same gmail with period and without period.

I check if the submitted email is '@gmail'.
If so I remove any period in the email before it is sent to database.

[Weedpacket]

Don't forget that "@googlemail.com" is equivalent to "@gmail.com".