如何获取目录中的子目录列表？

import 'dart:io';
void main() async {
  // Get the system temp directory.
  var systemTempDir = Directory.systemTemp;
  // List directory contents, not recursing into sub-directories,
  // not following symbolic links.
  await for (var entity in
      systemTempDir.list(recursive: false, followLinks: false)) {
    print(entity.path);
  }
}

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