One or two numeric digits Regex

Question

I have the below code. It works only when I have 2 digits. If I have 1 digit doesn't work. I want to work in both cases: one or two digit.
var numberRegex = /^[1-9][0-9]$/;
I've tried something like this but unfortunately doesn't work:
var numberRegex = /^[1-9]?[1-9][0-9]$/;
Thanks for support.

score 35 · Accepted Answer · answered May 27 '12 at 02:44

35

Try this one out:

/^\d{1,2}$/;

Reading what you have it looks like you don't want to accept numbers like 01.

/^\d{1}|[1-9]\d{1}$/;

answered May 27 '12 at 02:44

Joel Etherton

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The second regex isn't quite right. `|` has lower precendence than `^` and `$`. You can also simplify by just making the `[1-9]` optional. `/^[1-9]?\d{1}$/` – Matt Ball May 27 '12 at 02:51
Just realized you can do even better - `\d{1}` is redundant, and equivalent to `\d`. – Matt Ball May 27 '12 at 02:58
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I'd go with `/^[1-9]?\d$/` No need for alternation, just make the leading digit optional. – Mark Reed May 27 '12 at 03:02
@MarkReed, your decision is cool but one digit zero is valid for your Regex – iamarsey Oct 28 '15 at 09:43
Yes. 0 by itself is valid. That's intentional. – Mark Reed Oct 28 '15 at 12:15

score 2 · Answer 2 · answered May 27 '12 at 03:52

2

try this regex: /^[1-9]\d{0,1}$/

answered May 27 '12 at 03:52

Darshana

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score 2 · Answer 3 · answered Jul 28 '16 at 16:58

2

Try this.

/^[0-9]|[0-9][0-9]$/

This should do the job. Using an Or operator does it.

answered Jul 28 '16 at 16:58

Vishak Kavalur

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score 2 · Answer 4 · edited Apr 01 '18 at 16:20

2

This works:

/^([0-9]{0,1}([1-9][0-9]){0,2})$/

edited Apr 01 '18 at 16:20

glennsl

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answered Apr 01 '18 at 16:00

Ozz

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One or two numeric digits Regex

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