RE: Historical Question

On Fri, 21 Nov 2003, Scott Johnson wrote:

> I asked about email validation a few weeks ago. And it can become a very deep
> subject in a hurry.  Everybody has their own way of doing it.  The best way to
> do it is to use something called Regular Expression.  Which RPGIV does not
> currently support.

First of all, I disagree that a Regular Expression is the "best" way to do
this.  In fact, I'd be willing to wager that your regular expression does
not correctly handle the e-mail address.

Second, you CAN use Regular Expressions in RPG by calling the RegComp,
RegExec, etc routines from the ILE C runtime library.


> I did eventually find some Delphi code that was very promising.  I took
> that and converted it to RPG IV.  Below are the results.  Now this just
> does "syntax" checking. It will not check if the email address is really
> valid.  I have not thoroughly checked this code to make sure it works in
> ALL cases, but it has work for me so far.  So if you find any bugs or
> such, please let me know.

Actually, that code looks pretty good...   I'm not going to fully analyze
it and compare it against the standards, but the state machine that it
uses appears to take things like quotes into account, which means that
it'll work much better than the Regular Expression methods that I've seen.

You might be interested in that VALMAIL service program that I mentioned
earlier in this thread.  It does more or less the same thing that your
validation program is doing, except that it also looks up the domain name
and makes sure that it exists...

http://www.iseriesnetwork.com/resources/clubtech/index.cfm?fuseaction=ShowNewsletterIssue&ID=17632

Good Luck