Hey I want to remove character/word or sentence from string.
For example
val string = "Hey 123"
or
val string = "Hey How are you 123"
or
val string = "Hey!! How are you 123"
and output
string = 123
>Solution :
If you only want the digits:
val result = string.filter { it.isDigit() }
Alternatively if you want to omit letters (and maybe also whitespace):
val result = string.filter { !it.isLetter() }
val result = string.filter { !it.isLetter() && !it.isWhitespace() }