Problem validating e-mail with RegEx using preg_match() in PHP

Question

I can't get working a preg_match() in PHP to validate an e-mail address. I've tested the RegEx expression that I've found on Internet with the http://www.regexer.com tool and works fine with the same input I'm using on my PHP application.

RegEx expression:

^([a-z0-9\+_\-]+)(\.[a-z0-9\+_\-]+)*@([a-z0-9\-]+\.)+[a-z]{2,6}$

Regexer: http://regexr.com?2sr2a

And I'm applying it like this in PHP:

$email   = "[email protected]";
$pattern = "/^([a-z0-9\+_\-]+)(\.[a-z0-9\+_\-]+)*@([a-z0-9\-]+\.)+[a-z]{2,6}$/ix";

if (false == preg_match($pattern, $email))
    echo "false";

And of course, I get a false with this e-mail and others that I've tested. The expression I think is well formed because on regexer I can test and it works. What I'm applying incorrectly?

Thank you in advance!

Gazillion duplicates - use PHP's native filter_var instead of a regex — Gordon
– Gordon, Commented Jan 4, 2011 at 16:45

SirDarius · Accepted Answer · 2011-01-04 16:46:36Z

1

Backslash characters need to be properly escaped by doubling them like this:

$pattern = "/^([a-z0-9\\+_\\-]+)(\\.[a-z0-9\\+_\\-]+)*@([a-z0-9\\-]+\\.)+[a-z]{2,6}$/ix";

Using this pattern, preg_match correctly returns 1.

answered Jan 4, 2011 at 16:46

SirDarius

43.3k8 gold badges92 silver badges106 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

mario Over a year ago

They don't normally. Backslashes are only stripped when they preceed another backslash, double quote, $, octal literals, or one of the ascii escapes \r \n \t. print "\." will print \.

SirDarius Over a year ago

Although it's not mandatory to escape backslashes, it is highly recommended to do so in double-quoted strings, especially if you might accidentally insert a character causing the creation of a valid escape sequence.

user562854 · Accepted Answer · 2011-01-04 16:46:30Z

0

I am not sure what is wrong in your code but here you have a fully functional php function for checking an email address:

function is_validemail($email) 
{
     return preg_match('/^[\w.-]+@([\w.-]+\.)+[a-z]{2,6}$/is', $email);
}

$email = "[email protected]";

if(is_validemail($email)) { echo ("email validated"); } else { echo ("invalid email given"); }

Hope it helps!

answered Jan 4, 2011 at 16:46

user562854

Collectives™ on Stack Overflow

Problem validating e-mail with RegEx using preg_match() in PHP

2 Answers 2

2 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related