I think your best bet is to have them enter their email, and hope for the best. For verification, pattern match for something that looks like a valid email. Since there are many possibilities: foo@bar.(com | org | edu | gov| uk | org.gy), first.last@foo.bar.com, etc, you'll have to be very creative. As a matter of fact, Mastering Regular Expressions has 10 pages dedicated to this problem, and uses it as a "Let's put everything we've learned in the entire book" example. At the very least, you should make sure there's a '@' and at least one '.' in the address.

If you wanna be more picky, you can start a background mailer that sends a test mail to the address. If it bounces, the address is bogus. This'll look a little odd on their end, and I can't guarantee how they'll react, but it should work.

-Logan
"What do I want? I'm an American. I want more."

In reply to Re: Getting Email environment address by logan
in thread Getting Email environment address by Anonymous Monk

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