updated regex for email validation

[Jim Dornbush]

Has anyone seen an updated regex expression from Microsoft for the email
validation expression so that single quotes are allowed?

I've been using the canned regex for emails, but recently been informed by a
customer that the single quote is allowed as part of the email address (Mr.
O'Leary).

I prefer using the un-modified version from the framework, but will update
my local code regardless.

[Greg Bacon]

In article <u#************ **@TK2MSFTNGP06 .phx.gbl>,
Jim Dornbush <jd*******@xrit e.comwrote:

: Has anyone seen an updated regex expression from Microsoft for the
: email validation expression so that single quotes are allowed?
:
: I've been using the canned regex for emails, but recently been
: informed by a customer that the single quote is allowed as part of the
: email address (Mr. O'Leary).
:
: I prefer using the un-modified version from the framework, but will
: update my local code regardless.

In <11************ *@corp.supernew s.com>, I described a stopgap that
you might consider in a pinch.

The idea is to dump the regular expression from the Email::Address CPAN
module. Code below.

Moral: regular expressions are poor substitutes for parsers.

Enjoy,
Greg

using System;
using System.Text.Reg ularExpressions ;

using NUnit.Framework ;

namespace Application
{
public interface SyntaxChecker
{
bool WellFormed(stri ng input);
}

public class EmailAddressChe cker : SyntaxChecker
{
// derivative of work with the following copyright and license:
// Copyright (c) 2004 Casey West. All rights reserved.
// This module is free software; you can redistribute it and/or
// modify it under the same terms as Perl itself.

// see http://search.cpan.org/~cwest/Email-Address-1.80/

#region dumped regular expression
private static string gibberish = @"
(?-xism:(?:(?-xism:(?-xism:(?-xism:(?-xism:(?-xism:(?-xism:\
s*\((?:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^
\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+))
|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)+
|\s+)*[^\x00-\x1F\x7F()<>\[\]:;@\,.<DQ>\s]+(?-xism:(?-xism:\
s*\((?:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^
\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+))
|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)+
|\s+)*)|(?-xism:(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-xism:(
?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?
:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x
0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)+ |\s+)*<DQ>(?-xism:(?-xism:[
^\\<DQ>])|(?-xism:\\(?-xism:[^\x0A\x0D])))+<DQ>(?-xism:(?-xi
sm:\s*\((?:\s*( ?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xis
m:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\
]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\
s*)+|\s+)*))+)? (?-xism:(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?
-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:
\s*\((?:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[
^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)+ |\s+)*<(?-xism:(?-xi
sm:(?-xism:(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^(
)\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(
?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))
|)+)*\s*\)\s*)) +)*\s*\)\s*)+|\ s+)*(?-xism:[^\x00-\x1F\x7F()<

>\[\]:;@\,.<DQ>\s]+(?:\.[^\x00-\x1F\x7F()<>\[\]:;@\,.<DQ>\s]

+)*)(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+))
|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:
(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s
*\)\s*))+)*\s*\ )\s*)+|\s+)*)|( ?-xism:(?-xism:(?-xism:\s*\((?
:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x
0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+))|(?-xi
sm:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)+ |\s+)*
<DQ>(?-xism:(?-xism:[^\\<DQ>])|(?-xism:\\(?-xism:[^\x0A\x0D]
)))+<DQ>(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\
]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-x
ism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+
)*\s*\)\s*))+)* \s*\)\s*)+|\s+) *))\@(?-xism:(?-xism:(?-xism:(
?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?
-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^
()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s
*\)\s*)+|\s+)*( ?-xism:[^\x00-\x1F\x7F()<>\[\]:;@\,.<DQ>\s]+(
?:\.[^\x00-\x1F\x7F()<>\[\]:;@\,.<DQ>\s]+)*)(?-xism:(?-xism:
\s*\((?:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[
^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+)
)|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)
+|\s+)*)|(?-xism:(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-xism:
(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((
?:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\
x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)+ |\s+)*\[(?:\s*(?-xism:(?-x
ism:[^\[\]\\])|(?-xism:\\(?-xism:[^\x0A\x0D])))+)*\s*\](?-xi
sm:(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:
\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(
?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+
)*\s*\)\s*)+|\s +)*)))>(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-
xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\
s*\((?:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^
\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)+ |\s+)*))|(?-xism:(?-x
ism:(?-xism:(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^
()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *
(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D])
)|)+)*\s*\)\s*) )+)*\s*\)\s*)+| \s+)*(?-xism:[^\x00-\x1F\x7F()
<>\[\]:;@\,.<DQ>\s]+(?:\.[^\x00-\x1F\x7F()<>\[\]:;@\,.<DQ>\s
]+)*)(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+)
)|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism
:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\
s*\)\s*))+)*\s* \)\s*)+|\s+)*)| (?-xism:(?-xism:(?-xism:\s*\((
?:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\
x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+))|(?-x
ism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)+ |\s+)
*<DQ>(?-xism:(?-xism:[^\\<DQ>])|(?-xism:\\(?-xism:[^\x0A\x0D
])))+<DQ>(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\
\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-
xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)
+)*\s*\)\s*))+) *\s*\)\s*)+|\s+ )*))\@(?-xism:(?-xism:(?-xism:
(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(
?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[
^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\
s*\)\s*)+|\s+)* (?-xism:[^\x00-\x1F\x7F()<>\[\]:;@\,.<DQ>\s]+
(?:\.[^\x00-\x1F\x7F()<>\[\]:;@\,.<DQ>\s]+)*)(?-xism:(?-xism
:\s*\((?:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:
[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+
))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*
)+|\s+)*)|(?-xism:(?-xism:(?-xism:\s*\((?:\s *(?-xism:(?-xism
:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\(
(?:\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A
\x0D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)+ |\s+)*\[(?:\s*(?-xism:(?-
xism:[^\[\]\\])|(?-xism:\\(?-xism:[^\x0A\x0D])))+)*\s*\](?-x
ism:(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?>[^()\\]+))|(?-xism
:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:\s *(?-xism:(?-xism:
(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|)+)*\s*\)\s* ))
+)*\s*\)\s*)+|\ s+)*))))(?-xism:\s*\((?:\s *(?-xism:(?-xism:(?

>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0D]))|(?-xism:\s*\((?:

\s*(?-xism:(?-xism:(?>[^()\\]+))|(?-xism:\\(?-xism:[^\x0A\x0
D]))|)+)*\s*\)\s* ))+)*\s*\)\s*)* )"
.Replace("<DQ>" , "\"")
.Replace("\t", "")
.Replace(" ", "")
.Replace("\r", "")
.Replace("\n", "");
#endregion

private static Regex mailbox =
new Regex(gibberish , RegexOptions.Ex plicitCapture);

public bool WellFormed(stri ng address)
{
return mailbox.IsMatch (address);
}
}

[TestFixture]
public class Test
{
private SyntaxChecker checker = null;

[SetUp]
public void SetUp()
{
checker = new EmailAddressChe cker();
}

[Test]
public void SimpleAddress()
{
Assert.IsTrue(c hecker.WellForm ed("fo*@example .com"));
}

[Test]
public void MustHaveLocalAn dDomain()
{
Assert.IsFalse( checker.WellFor med("justlocal" ));
}

[Test]
public void AmpersandInLoca lPart()
{
Assert.IsTrue(c hecker.WellForm ed("\"foo & bar\"@example.c om"));
}

[Test]
public void PhraseAndAngles ()
{
Assert.IsTrue(c hecker.WellForm ed("Joe <jo*@example.co m>"));
}

[Test]
public void AddressAndComme nt()
{
Assert.IsTrue(c hecker.WellForm ed("jo*@example .com (Joe)"));
}

[Test]
public void ContainsSingleQ uoteInParenComm ent()
{
Assert.IsTrue(c hecker.WellForm ed("ol****@exam ple.com (Mr. O'Leary)"));
}

[Test]
public void ContainsSingleQ uoteInBareComme nt()
{
Assert.IsTrue(c hecker.WellForm ed("Mr. O'Leary <ol****@example .com"));
}

[Test]
public void ContainsSingleQ uoteInLocalPart ()
{
Assert.IsTrue(c hecker.WellForm ed("o'*****@exa mple.com"));
}
}
}
--
You have to choose between trusting the natural stability of gold and the
honesty and intelligence of members of the government. With due respect for
these gentlemen, I advise you, as long as the capitalist system lasts, to
vote for gold. -- George Bernard Shaw