Question

I want to detect emails in text format so that I can put an anchor tag over them with mailto tag in anchor. I have the regex for it but the code also detects emails which are already encapsulated by anchor tag or is inside the anchor tag mailto parameter.

My regex is:

([\w-]+(\.[\w-]+)*@([a-z0-9-]+(\.[a-z0-9-]+)*?\.[a-z]{2,6}|(\d{1,3}\.){3}\d{1,3})(:\d{4})?)

But it detects 3 matches in the following sample text:

ttt <a href='mailto:[e-mail]'>[e-mail]</a> abc [e-mail]

I want only [e-mail] to be matched by the regex.

Answer 1

Very similar to my previous answer to your other question, try this

(?<!(?:href=['"]mailto:|<a[^>]*>))(\b[\w-]+(\.[\w-]+)*@([a-z0-9-]+(\.[a-z0-9-]+)*?\.[a-z]{2,6}|(\d{1,3}\.){3}\d{1,3})(:\d{4})?)

The only thing that is really different is the word boundary \b before the start of the email.

See a similar expression here on Regexr, its not exactly the same, because Regexr does not support alternations and infinite length in the lookbehind.