regex to find numbers with unique digits

Question

I want to find 10 digit numbers with no repeat digits, for example:

1123456789 //fail, there are two 1\'s
6758951230 //fail, there are two 5\'s
6789012345 //         


        

Answer 1

lancemanfv regex reference https://stackoverflow.com/a/12870549/1366360 is a great one, but the suggested regex is slightly off.

Instead try

^(?:([0-9])(?!.*\1)){10}$ 

This will match any string that begins and ends with 10 digits that are all different.

If you want to check (and extract) if a longer string contains a 10 digit number with each number different use this

((?:([0-9])(?!.*\2)){10})*

You can then use a numbered reference to extract the matching number