SGuerreiro
SGuerreiro

Reputation: 57

Regex Number reservations

Good afternoon, I am creating a form with a number reservation field, for the user to pick. The system i had would only allow the reservation number by number, example: 1,2,3 and it would book the numbers 1,2 and 3.

Now i would like to add the option to book several numbers at once, example: 1-5,9,10and in this case it would book numbers 1 to 5, 9 and 10.

I'm using the following regex code, but it's not working as I want

^\d{1,5}(?:-\d{1,5})*(?:,\d{1,5})*(?:,\d{1,5}-\d{1,5})*(?:-\d{1,5},\d{1,5})*$

The problem with this code is whenever the user inserts two 1-3,4-6 it only allows one more number. For example 1-3,4-6,2,3 shows error when the ,3 is inserted.

There is also a problem where it allows to write several dashes without commas example 1-3-6-8-9

Upvotes: 0

Views: 70

Answers (1)

Casimir et Hippolyte
Casimir et Hippolyte

Reputation: 89584

perhaps something like this:

\A\d{1,5}(?:-\d{1,5})?(?:,\d{1,5}(?:-\d{1,5})?)*\z

The idea:

  • the range is optional (?:-\d{1,5})? (and follows the first number)
  • The group, that contains a comma followed by a number or a range, can occur zero or more times

Note that a problem can't be solved by regex since 6-4 or 1-5,2,3,4 are always possible. So you will need sooner or later to explode the string and to check if numbers and ranges are coherent.

Upvotes: 1

Related Questions