HarmonyOS使用file进行写入json数据, 读取后中文乱码. 这种应该如何处理

async writeDataAsync(path: string, content: ArrayBuffer | string): Promise<void> { 
  let fd = (await fs.open(path, fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE)).fd 
  let stat = await fs.stat(path) 
  await fs.write(fd, content, { offset: stat.size }) 
  await fs.close(fd) 
}

readFile(path: string): ArrayBuffer { 
  let fd = fs.openSync(path, fs.OpenMode.READ_WRITE).fd; 
  let length = fs.statSync(path).size 
  let buf = new ArrayBuffer(length); 
  fs.readSync(fd, buf) 
  return buf 
}

export function arrayBufferToString(buffer: ArrayBuffer): string { 
  return String.fromCharCode.apply(null, new Uint8Array(buffer)); 
}