getRandomKey method
Implementation
String getRandomKey(int length) {
const _chars = 'abcdefghijklmnopqrstuvwxyz1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ';
return String.fromCharCodes(
Iterable.generate(
length, (_) => _chars.codeUnitAt(_rnd.nextInt(_chars.length))
)
);
}