How faulty checking for valid email addresses can hurt you
1–10 of 18 posts
Re: How faulty checking for valid email addresses can hurt you
#2My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. Validating against the whole range of possible address content is near pointless. The warning simply asks the user to check their email in case of errors but allows a page submission following the display of that warning.
Re: How faulty checking for valid email addresses can hurt you
#3My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. Validating against the whole range of possible address content is near pointless. The warning simply asks the user to check their email in case of errors but allows a page submission following the display of that warning.
The problem is that the RFC is amazingly permissive : almost anything goes in email adresses, including whitespace! A RFC-compliant regex is incredibly complex [1]. Furthermore, one would need to read not one, but five RFCs in order to grok everything:
http://tools.ietf.org/html/rfc5322
http://tools.ietf.org/html/rfc3696
http://tools.ietf.org/html/rfc5321
http://tools.ietf.org/html/rfc4291#section-2.2
http://tools.ietf.org/html/rfc1123#section-2.1
[1] Great overview of the problem, plus a PHP validator. http://www.dominicsayers.com/isemail/
Re: How faulty checking for valid email addresses can hurt you
#4My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. Validating against the whole range of possible address content is near pointless. The warning simply asks the user to check their email in case of errors but allows a page submission following the display of that warning.
My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use.
My policy on validating email addresses is "if I send you an email and it arrives, your email address is valid".
Why do you need to "validate" an email address? Knowing that an address is syntactically valid doesn't do anything to confirm that it will reach the intended target.
Re: How faulty checking for valid email addresses can hurt you
#5My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. Validating against the whole range of possible address content is near pointless. The warning simply asks the user to check their email in case of errors but allows a page submission following the display of that warning.
My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. My policy on validating email addresses is "if I send you an email and it arrives, your email address is valid". Why do you need to "validate" an email address? Knowing that an address is syntactically valid doesn't do anything to confirm th…
You are correct - but - at your initial point of contact you have (perhaps) a single opportunity to make contact with your prospective customer. You should do all you can (without boring or annoying your prospect) to capture enough accurate information to ensure that the next step succeeds.
I agree - long term relationships are built on (in the context of this conversation) an exchange of emails but why blow it at the first hurdle?
Re: How faulty checking for valid email addresses can hurt you
#6My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. Validating against the whole range of possible address content is near pointless. The warning simply asks the user to check their email in case of errors but allows a page submission following the display of that warning.
My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. My policy on validating email addresses is "if I send you an email and it arrives, your email address is valid". Why do you need to "validate" an email address? Knowing that an address is syntactically valid doesn't do anything to confirm th…
[deleted]
Re: How faulty checking for valid email addresses can hurt you
#7My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. Validating against the whole range of possible address content is near pointless. The warning simply asks the user to check their email in case of errors but allows a page submission following the display of that warning.
My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. My policy on validating email addresses is "if I send you an email and it arrives, your email address is valid". Why do you need to "validate" an email address? Knowing that an address is syntactically valid doesn't do anything to confirm th…
Agreed. At [old job] we saw a lot of user-entered e-mail addresses that were "correct" (according to so-called validators) but wrong, like "www.screenname@aol.com" or "example@yahoo".
Re: How faulty checking for valid email addresses can hurt you
#8I gave up validating an email address a long time ago. Now all I will do is sanitize it to be safe from malicious attempts. The tipping point for me was trying to decipher an unreasonably long regular expression written months prior to find out why someone's funky address (like the author's) was failing -- wasted time.
You can try, but you can't prevent people from doing dumb things, and in the attempt you end up potentially making mistakes like in the case of the article. Users will always do something unanticipated. With that in mind I only validate the things that really matter (e.g. credit card numbers, social security numbers, etc.). If someone wants to enter "jane at aol" as their address, I have to think, "is this going to a problem for my company?" If not, don't bother to try to fix it.
Re: How faulty checking for valid email addresses can hurt you
#9My current policy on validating email addresses is to issue a warning if a given email address fails a check against a standard that covers the vast majority of addresses in use. Validating against the whole range of possible address content is near pointless. The warning simply asks the user to check their email in case of errors but allows a page submission following the display of that warning.
Mine is not to re-write the wheel. Writing a correct email address is indeed non-trivial, but there's at least one well known module written by someone who's actually read the RFCs and won't trash users using plussing and minusing. Use that, don't write your own.
Re: How faulty checking for valid email addresses can hurt you
#10There's no way to get around invalid email addresses. Anybody can put in something like asdhsouhdosd@ahsoufhsdof.com and it would pass most regex checks. I think the best solution is to just check for an "@" sign and a "." after it.