import 'dart:math'; class RandomStringGenerator { static const _chars = 'AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz1234567890'; static Random rnd = Random(); static String getRandomString(int length) => String.fromCharCodes(Iterable.generate( length, (_) => _chars.codeUnitAt(rnd.nextInt(_chars.length)))); static String getRandomStringLines(int lines, int length) { List result = []; for (var i = 0; i < lines; i++) { result.add(getRandomString(length)); } return result.join('\n'); } }