Question

I need to create a regexp to match strings like this 999-123-222-…-22
The string can be finished by &Ns=(any number) or without this… So valid strings for me are

999-123-222-...-22
999-123-222-...-22&Ns=12
999-123-222-...-22&Ns=12

And following are not valid:

999-123-222-…-22&N=1

I have tried testing it several hours already… But did not manage to solve, really need some help

Answer 1

Not sure if you want to literally match 999-123-22-...-22 or if that can be any sequence of numbers/dashes. Here are two different regexes:

/^[\d-]+(&Ns=\d+)?$/

/^999-123-222-\.\.\.-22(&Ns=\d+)?$/

The key idea is the (&Ns=\d+)?$ part, which matches an optional &Ns=<digits>, and is anchored to the end of the string with $.