如何在反应本机中以json格式获取excel文件数据

Question

如何在react native中获取json格式的excel表格数据？

const reader = new FileReader();

reader.onload =(evt)=>{
  // evt = on_file_select event
  /* Parse data */
  console.log("evt",evt)
  const bstr = evt.target.result;
  const wb = XLSX.read(bstr, { type: "binary" });
  /* Get first worksheet */
  const wsname = wb.SheetNames[0];
  const ws = wb.Sheets[wsname];
  /* Convert array of arrays */
  const data = XLSX.utils.sheet_to_csv(ws, { header: 1 });
  /* Update state */
  console.log("Data>>>" + data);// shows that excel data is read
  console.log(convertToJson(data)); // shows data in json format
};
**reader.readAsBinaryString();**

我得到了 reader.readAsBinaryString();未定义