Flutter:我在Flutter中将数据保存到文件中，但如何防止数据写入?

Question

我正在将数据打印到文件中，但该数据已被覆盖。如何在一个文件中收集所有数据

Future<String?> get _localPathBLE async {
final directory = await getExternalStorageDirectory();
return directory?.path;
}
Future<File> get _localFile async {
final path = await _localPathBLE;
var date =
DateUtil.instance.dateParseToString(DateEnum.FULL, DateTime.now());
return File('$path/DATA.csv');
}
Future<void> writeBLE(List<List<double>> acc3d) async {
final file = await _localFile;
String csv = const ListToCsvConverter().convert(acc3d);
// Write the file
return file.writeAsStringSync(csv);
}

Answer 1

为了将字节附加到现有文件，传递FileMode。附加为可选模式参数。

详情请参见writeAsStringSync。

Answer 2

Future<void> writeBLE(List<List<double>> acc3d) async {
final file = await _localFile;
String csv = const ListToCsvConverter().convert(acc3d);
// Write the file
return file.writeAsStringSync(csv + 'n',
mode: FileMode.append, flush: true);
}