createRandomString function
Implementation
String createRandomString(int length) {
const letters =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~";
Random _rnd = Random();
return String.fromCharCodes(Iterable.generate(
length, (_) => letters.codeUnitAt(_rnd.nextInt(letters.length))));
}