How to match all strings that has only one dot using regular expression

Question

I need to capture strings containing only one dot. String will mostly contains domain names like

test.com, fun.test.com, lesh.test.com.

I need to check only the first one and to ignore the string that has more than one dots.

How can I do this using regex?

Negating the match is faster i.e. No match `\..*\.` and string is ok. — , Dec 11 '19 at 22:20
For must contain a dot, use a string method to see if it contains a dot first, then validate no dup dots by negating the match i.e. no match `\..*\.` and string is ok. — , Dec 12 '19 at 17:21
The speed difference can be seen by given an equal sample of 2 passes and 2 fails out of 4 total `asssssssf.asssssssf \n assss.sssf.asssssssf \n asssssssf.asssssssf \n assss.sssf.asssssssf` the speed difference : `Regex1: \..*\. Completed iterations: 50 / 50 ( x 1000 ) Matches found per iteration: 2 Elapsed Time: 0.20 s, 202.78 ms, 202778 µs Matches per sec: 493,150 Regex2: ^[^.]+\.[^.]+$ Options: < m > Completed iterations: 50 / 50 ( x 1000 ) Matches found per iteration: 2 Elapsed Time: 0.37 s, 373.61 ms, 373605 µs Matches per sec: 267,662` — , Dec 12 '19 at 17:31

score 0 · Accepted Answer · answered Dec 11 '19 at 22:12

0

Like this :

^[^.]+\.[^.]+$

answered Dec 11 '19 at 22:12

Gilles Quenot

1 Answers1