Re: Define your own e-mail validation in DNN 4.5

I've noticed users with a - (dash) in their email address failed as well. had to edit the DB for them directly. *cough*

For instance my-email@domain.com was invalid.

So it's nice we can edit this ourselves (if I can figure it out too!)

Re: Define your own e-mail validation in DNN 4.5

I am not a regex expert either, but it seems like a two-stage evaluation would be best:
1. evaluate with a regex for the undesired domain names -- T or F determines passing to test #2 below
2. evaluate with a regex to see if it is a valid email format -- T or F determines what to do next
I know there exists DNS testing on the domain, building this into the email validation would be very nice if you or someone can do it...
Thank you, Tom

Re: Define your own e-mail validation in DNN 4.5

ErikVB: 'what if i wanted to exclude some domains, like yahoo, hotmail etc.'

The following links provide the basics.

VBScript User's Guide:
http://msdn2.microsoft.com/en-us/library/sx7b3k7y(vs.80).aspx

Introduction to Regular Expressions (Scripting):
http://msdn2.microsoft.com/en-us/library/6wzad2b2(VS.80).aspx

.NET Framework Regular Expressions:
http://msdn2.microsoft.com/en-us/library/hs600312(vs.80).aspx

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Validation:
http://msdn2.microsoft.com/en-us/asp.net/aa336647.aspx

Here, you find the following fragment:

ControlToValidate="email"
runat="server"
ValidationExpression="\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*">
ThThe email address appears to be of an incorrect format


I haven't checked it, so it's on you...

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For more information, here's a search for "valid email":
http://search.msdn.microsoft.com/search/default.aspx?__VIEWSTATE=&query=%22valid+email%22&siteid=0&tab=0

Back to topic. In order to exclude (ban) email addresses, I would prefer a blacklist. Making things nice, I guess DNN should have editable blacklists for IP's, domains, email addresses, usernames (e.g. admin, moderator, webhost, webmaster, b***h, f***, f***you, WeF***You, etc. ), etc. Such a blacklisting functionality makes Admins day easier, right?

Happy Coding!

Re: Define your own e-mail validation in DNN 4.5

Here's another piece (not tested):
http://www.asp.net/ControlGallery/ControlDetail.aspx?Control=2035&tabindex=0

Happy Coding!

Re: Define your own e-mail validation in DNN 4.5

Sorry, I've posted the wrong link in my last post!!!

Here's the correct link:
http://blogs.msdn.com/larryosterman/archive/2005/01/07/348548.aspx

And the answer can be found here:
http://blogs.msdn.com/larryosterman/archive/2005/01/10/350135.aspx

I apologize any inconvenience!

Happy Coding!

Re: Define your own e-mail validation in DNN 4.5

Here's another good read:
http://tools.ietf.org/html/rfc3696

Re: Define your own e-mail validation in DNN 4.5

Nice! This one:
^[\w\d_\+-]+(\.[\w\d_\+-]+)*@(?:[a-zA-Z0-9-]+\.)+(?:[A-Z]{2}|com|org|net|biz|info|name|aero|biz|info|jobs|museum|name)$
would also filter out email addresses starting with a dot

Timo

Re: Define your own e-mail validation in DNN 4.5

Well, here's another good read:
http://hexillion.com/email_validation/

However, after spending some hours on the e-mail validation issue, two conclusions left over.

1. The e-mail address specification allows plenty of valid e-mail addresses that will be rejected by the most 'regex' verifications. In such cases, it would prevent users from using their valid e-mail addresses.

2. The 'live' e-mail-address test confirms the existence of a domain only, but in the most cases not the e-mail address itself (this would be an open door for spammers to check the validity of an e-mail address, therefore, the most e-mail hosts also acknowledge non-existing e-mail addresses).

3. To make sure that an e-mail address is valid, an e-mail has to be sent to the user and the user must confirm this e-mail address by typing in the correct verification code in the registration/login form.

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The main question is now. Isn't it better that the user has to type in the e-mail address twice in order to provide the user the possibility to prevent input errors? I guess that's the main reason for the e-mail address verification..

Note: In order to make the user input more reliable, the input should be hidden like it is with the password input. In addition, the copy/paste feature should be deactivated, so that the user 'must' type in the e-mail address twice.

The second question is what to do with registered users whose e-mail address is invalid at a later time (sending an e-mail to the given e-mail address fails)?

Note: I would prefer the solution that they have to provide a new e-mail address when logging in the next time after sending an e-mail failed. In such a case, the e-mail address verification process (verification code) should be available as option.

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Anyway, the e-mail address verification process (verification code) is always the only way in order to make sure that the user has provided a valid e-mail address to which he/she has access. Everything else is not reliable. In other words, I would abandon the regex verification in favor of the double input idea, the e-mail verification process, and the blacklists (in order to ban some IP's, domains, e-mail addresses, usernames, etc.) I've mentioned before. Agreed, that's my point of view.

Happy Coding!

Re: Define your own e-mail validation in DNN 4.5

Hi Erik,

Your regex is wrong ! ;-) I have already make a post on Gemini (Issue DNN-5011) about this problem. Try this email o your regex : john-doe@dutch.nl
Your regex reject it because the - between john and doe, and the country in lower case is rejected too.
You can use this one instead :
^[a-zA-Z0-9._%\-+']+@(?:[a-zA-Z0-9\-]+\.)+(?:[a-zA-Z]{2}|com|org|net|biz|info|name|aero|biz|info|jobs|museum|name)$

Gilles

Re: Define your own e-mail validation in DNN 4.5

@erik
Your right I cleaned it up a bit too much, for testing...
Timo

Re: Define your own e-mail validation in DNN 4.5

And what about foreign country domains like .ca, .ru, .cn, etc.??

There is a very good email validation library at aspemporium.com, with a basic javascript version and a C# version that takes into account all the country variations but I do not know how to convert it to VB or JS.

Thank you, Tom

Re: Define your own e-mail validation in DNN 4.5

Is there any way to get something similar to these validation improvements into a 4.4 installation? A config file that can be altered? Or a simple source amendment? My site users are complaining that they cannot register addresses with dashes in them.

Re: Define your own e-mail validation in DNN 4.5

bmolzen: you might have figured it out by now but if you want a dash (-) to validate in an email address put a '-' at the very beginning of the validation expression:

\b[-a-zA-Z0-9._%-+']+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}\b

Other '-' are interpreted as ranges, putting it at the beginning overrides this

Re: Define your own e-mail validation in DNN 4.5

any particular reason why |edu| is excluded from the exclusive list of domain extensions?

Re: Define your own e-mail validation in DNN 4.5

If anyone is still trying to use this for reference, note that you need to add a couple more top-level domains, making the last section into |aero|arpa|asia|biz|cat|com|coop|edu|gov|info|int|jobs|mil|mobi|museum|name|net|org|pro|root|tel|travel|cym|geo|post

I just got bit by not having edu in there, also added gov, arpa, int, mil, asia, cat, coop, mobi, pro, root, tel, travel, and three proposed domains, post, geo, and cym. These come mainly from http://www.iana.org/gtld/gtld.htm.

Re: Define your own e-mail validation in DNN 4.5

Would be great if the regex winner got impliemented by default in an upcoming DNN release :)... Great stuff!!! Email validation I've always found to be a total nightmare :).

Re: Define your own e-mail validation in DNN 4.5

I created a regexp that seems to work (at least for me). Feel free to add additional valid characterers between the []

^[a-zA-Z](?:[-a-zA-Z0-9_]|\.(?!\.))*(?<=[-a-zA-Z0-9_])@(([-&a-zA-Z0-9_]+)(\.?(?!\.)))+?(?<=\.[-.&a-zA-Z0-9]+)(?<=[-&a-zA-Z0-9]{2,})$