Regex for letters numbers space and backslash in kotlin

Issue

I want to use regex in kotlin to allow only this kind of strings each strings is length of 15 and can be of any long I just kept 3 numbers as example.

"123456789101236 \n 123456789101237 \n 123456789101238"

Solution

You may use the following regex pattern:

\d{15}(?: \n \d{15})*

This assumes that you want only numbers of length 15. If you want any character, then use .{15} in place of \d{15}.

Kotlin code:

val input = "123456789101236 \n 123456789101237 \n 123456789101238";
val regex = "\\d{15}(?: \n \\d{15})*".toRegex()
if (regex.matches(input)) {
    println("MATCH")  // prints MATCH
}

Answered By - Tim Biegeleisen