REGEX To accept numbers separated by commas, but number range is 0-32767

Question

I need to write a regular expression for taking input like this

23,456,22,1,32767

i.e.

1. No commas allowed at the start or end.
2. Spaces may come before and/or start of comma for e.g. 23, 45,56 ,67 etc.
3. Ranges of each number should be 0-32767.

Currently I am using regular expression like this [0-9]+(,[0-9]+)*.

This allows for numbers separated by commas only ( not allowing spaces at all), and it does not check for the range of number.

Combings

You don't want to check the number range with regex, it will be relay unreadable – Sadie

codinghorror.com/blog/2008/06/… – Wartow

Answer 1

It's probably wise to do it in two steps. First check that the range is 0-99999:

^[0-9]{1,5}( *, *[0-9]{1,5})*$

Then parse the string to a list of integers using a general purpose programming language and check that x <= 32767 for each integer x.

Ionopause

+1, but you might want to add \s* around the comma to allow for spaces as Basmah asked. – Stanislaus

"\s*" or " *"? The question seems very unclear on this point. – Ionopause

Thanks Mark ! This was of help! – Combings

Mark, would you please tell me the regex for th to write a regular expression for taking input like this 23,456,22,1,32767 i.e. 1.No commas allowed at the start or end. 2.Spaces may come before and/or start of comma for e.g. 23, 45,56 ,67 etc.e following – Combings

what should I change in this just to accept numbers separated by commas and no spaces in between? – Zobias

how to make them non repeating – Tanatanach

Answer 2

You can validate a number range with a regex, but since you need to look at the textual representation of numbers, the regex will be hard to read:

0*(?:3276[0-7]|327[0-5][0-9]|32[0-6][0-9]{2}|3[01][0-9]{3}|[12][0-9]{4}|[1-9][0-9]{1,3}|[0-9])

matches an integer between 0 and 32767, with optional leading zeroes.

So your entire regex would be

^0*(?:3276[0-7]|327[0-5][0-9]|32[0-6][0-9]{2}|3[01][0-9]{3}|[12][0-9]{4}|[1-9][0-9]{1,3}|[0-9])(?: *, *0*(?:3276[0-7]|327[0-5][0-9]|32[0-6][0-9]{2}|3[01][0-9]{3}|[12][0-9]{4}|[1-9][0-9]{1,3}|[0-9]))*$

Now imagine you inherit that regex from a co-worker who has left your company years ago...Have fun :)

Therefore, take Mark's advice.

_{This answer is intended purely for educational purposes and does not constitute a recommendation to use a regex in this case.}

Stanislaus