multiline regex match

Question

Why the regex below not working for the text below

Regex:

(?=.*\berror\b)(?=.*\balarm\b).*

Text :

ns1.alarm.abc 
ns2.error.cdb

In other works how to do multiline regex match?

Multiline regex is often a mode which you set in your regex engine/tool. As for your pattern, the lookaheads look wrong to me. Why not just match a regular pattern? — Tim Biegeleisen, Nov 09 '17 at 02:12
What regex engine / language are you using? That's crucial if you want info on how to enable multiline mode — Mad Physicist, Nov 09 '17 at 02:30

Gurmanjot Singh · Accepted Answer · 2017-11-09T03:27:03.003

0

I think you are trying to find the strings containing either error or alarm and for that you can try the following:

Try this Regex:

(?=.*\b(?:error|alarm)\b).*

Click for Demo

Explanation:

(?=.*\b(?:error|alarm)\b) - Positive lookahead for checking the presence of the words - error OR alarm
.* - if the above condition is satisfied, match 0+ occurrences of all characters(except a newline character)

Your regex (?=.*\berror\b)(?=.*\balarm\b).* does not work as it is trying to find both the words error and alarm in the same line/input string. So, you needed to put an OR condition as shown above.

Update:

To match both, use this.

(?=[\s\S]*\berror\b)(?=[\s\S]*\balarm\b)[\s\S]* as shown HERE

edited Nov 09 '17 at 03:27

answered Nov 09 '17 at 02:58

Gurmanjot Singh

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Thanks but I need to find error and alarm in the entire text ( not just one line )> is there a better way to do this ? – Iamtheroot Nov 09 '17 at 03:17
@Iamtheroot Updated the answer. Let me know if it works for ya. – Gurmanjot Singh Nov 09 '17 at 03:38
Thanks Gurman. Exactly what I was looking for. – Iamtheroot Nov 09 '17 at 03:53

multiline regex match

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