如何获取系统时间戳，你知道吗？

try { 
  systemDateTime.getCurrentTime(true, (error, time) => { 
    if (error) { 
      console.info(`Failed to get currentTime. message: ${error.message}, code: ${error.code}`); 
      return; 
    } 
    console.info(`Succeeded in getting currentTime : ${time}`); 
  }); 
} catch(e) { 
  console.info(`Failed to get currentTime. message: ${e.message}, code: ${e.code}`); 
}