Javascript REGEX for Subdomain (Optional)-CodePudding

I am looking for a REGEX (JS) that I can use to match all subdomains for a domain as well as the TLD domain in email addresses.

Here is an example:

I would like to be able to match any the following:

But not match

[email protected]

By default we use something like:

/(.*)@(.*)canada\.ca/gm

But this matches all of the above. Would ideally like a single REGEX that will accomplish all of this.

CodePudding user response：

You could use

^[^\s@] @(?:[^\s@.] \.)*canada\.ca$

^ Start of string
[^\s@] Match 1 chars other than a whitespace char or @
@ Match literally
(?:[^\s@.] \.)* Match optional repetitions of 1 chars other than a whitespace char, @ or dot, and then match the .
canada\.ca Match canada.ca (Note to escape the dot to match it literally
$ End of string

Regex 101 demo.

const regex = /^[^\s@] @(?:[^\s@.] \.)*canada\.ca$/;
[
  "[email protected]",
  "[email protected]",
  "[email protected]",
  "[email protected]",
].forEach(s => console.log(`${s} --> ${regex.test(s)}`));

CodePudding user response：

An easier way is to simply anchor canada to a word boundary using \b, that way you can use your regex pretty much word for word:

.*@.*\bcanada\.ca