Regex / Pattern HTML email

Question

Is there a way to associate two regex ?

I have this one which prevents user to use this email (test@test.com)

pattern="^((?!test@test.com).)*$"

I also have one which validates email syntax

pattern="[a-z0-9._%+-]{3,}@[a-z]{3,}([.]{1}[a-z]{2,}|[.]{1}[a-z]{2,}[.]{1}[a-z]{2,})"

How to merge those two regex in order to prevent user to user test@test.com and to validate the email syntax ?

I tried to use an OR operator (single pipe) but I am missing something, it doesn't work ...

Thanks !

It would be much easier to validate email (e.g. via regex), and then just separately check that the email isn't "test@test.com" via plain string comparison. — Alex Shesterov, Apr 19 '18 at 09:39
Probably you want `pattern="(?!test@test.com$)[\w.%+-]{3,}@[a-z]{3,}\.[a-z]{2,}(?:\.[a-z]{2,})?"` — Wiktor Stribiżew, Apr 19 '18 at 09:40
Possible duplicate of [Regular Expressions: Is there an AND operator?](https://stackoverflow.com/questions/469913/regular-expressions-is-there-an-and-operator) — Alex Shesterov, Apr 19 '18 at 09:40
@WiktorStribiżew It works ! Could you please explain in an answer ? — Defoncesko, Apr 19 '18 at 09:43

Wiktor Stribiżew · Accepted Answer · 2018-04-19T09:55:18.210

It seems you may use

pattern="(?!test@test\.com$)[a-z0-9._%+-]{3,}@[a-z]{3,}\.[a-z]{2,}(?:\.[a-z]{2,})?"

Note that the HTML5 patterns are automatically anchored as they are wrapped with ^(?: and )$ at the start/end, so no need adding ^ and $ at the start/end of the pattern.

The (?!test@test\.com$) negative lookahead will fail the match if the input string is equal to the test@test.com string (unlike your first regex that only fails the input that contains the email).

The rest is your second pattern, I only removed {1} that are implicit and contracted an alternation group to a \.[a-z]{2,}(?:\.[a-z]{2,})? where (?:\.[a-z]{2,})? is an optional non-capturing group matching 1 or 0 sequences of . and 2 or more lowercase ASCII letters.

Add A-Z to the character classes to also support uppercase ASCII letters.

If I need this pattern to be supported by IE 11, do I need to add ^ and $ ? — Defoncesko, Apr 19 '18 at 09:52
@Defoncesko HTML5 adds `^` and `$` at the start/end automatically. This pattern will work the same in all browsers. — Wiktor Stribiżew, Apr 19 '18 at 09:55

Regex / Pattern HTML email

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