Add separator to string at every N characters?

Question

I have a string which contains binary digits. How to separate string after each 8 digit?

Suppose the string is:

string x = \"111111110000000011111111         


        

Answer 1

I did it using Pattern & Matcher as following way:

fun addAnyCharacter(input: String, insertion: String, interval: Int): String {
  val pattern = Pattern.compile("(.{$interval})", Pattern.DOTALL)
  val matcher = pattern.matcher(input)
  return matcher.replaceAll("$1$insertion")
}

Where:

input indicates Input string. Check results section.

insertion indicates Insert string between those characters. For example comma (,), start(*), hash(#).

interval indicates at which interval you want to add insertion character.

input indicates Input string. Check results section. Check results section; here I've added insertion at every 4th character.

Results:

I/P: 1234XXXXXXXX5678 O/P: 1234 XXXX XXXX 5678

I/P: 1234567812345678 O/P: 1234 5678 1234 5678

I/P: ABCDEFGHIJKLMNOP O/P: ABCD EFGH IJKL MNOP

Hope this helps.