readableFileSize method
Implementation
String readableFileSize({bool base1024 = true}) {
final base = base1024 ? 1024 : 1000;
if (this <= 0) return "0";
final units = ["bytes", "KB", "MB", "GB", "TB"];
int digitGroups = (log(this) / log(base)).round();
return "${NumberFormat("#,##0.#").format(this / pow(base, digitGroups))} ${units[digitGroups]}";
}