Regular Expression for null or Domain (Pattern) validation

Question

This is not working I am using following code to validate email for e.g

"email":{
"regex":"/^[a-zA-Z0-9_\.\-]+\@([a-zA-Z0-9\-]+\.)+[a-zA-Z0-9]{2,4}$/",
"alertText":"* Invalid email address"},

On this way I want to validate text box by regular expression. It should be Null or valid domain name like Google.com, example.com.

What sort of validation/form handling *framework* do you use? — Stefan Gehrig, May 19 '11 at 12:54
You've ask the same question: http://stackoverflow.com/questions/6058484/regular-expression-for-null-or-domain-pattern-validation — Toto, May 19 '11 at 13:12

score 0 · Answer 1 · answered May 19 '11 at 12:58

If you just want to make it optional, that means empty string or a string that meets your regex, then try this:

^(?:[\w.-]+\@([a-zA-Z0-9-]+\.)+[a-zA-Z0-9]{2,4})?$

I just put your regex into a non capturing group (?:)and make this group optional with the ? after the group.

And I simplified your character classes, [a-zA-Z0-9_] is the same than \w and escaping is for the most cases not needed within character clases.

score 0 · Answer 2 · answered May 19 '11 at 13:02

0

Producing a regular expression to validate an e-mail address is far from trivial.

You probably want to read something like this:

answered May 19 '11 at 13:02

ADW

score 0 · Answer 3 · edited May 23 '17 at 12:12

0

edited May 23 '17 at 12:12

Community

answered May 19 '11 at 13:28

Bhushan Kawadkar

3 Answers3