文件的internal路径问题

import axios from '@ohos/axios' 
import { FormData } from '@ohos/axios' 
import fs from '@ohos.file.fs'; 
 
// ArrayBuffer 
let formData = new FormData() 
let cacheDir = getContext(this).cacheDir 
try { 
  // 写入 
  let path = cacheDir + '/image_source.jpg'; 
  let file = fs.openSync(path, fs.OpenMode.CREATE | fs.OpenMode.READ_WRITE) 
  fs.writeSync(file.fd, "hello, world"); // 以同步方法将数据写入文件 
  fs.fsyncSync(file.fd); // 以同步方法同步文件数据。 
  fs.closeSync(file.fd); 
 
  // 读取 
  let file2 = fs.openSync(path, 0o2); 
  let stat = fs.lstatSync(path); 
  let buf2 = new ArrayBuffer(stat.size); 
  fs.readSync(file2.fd, buf2); // 以同步方法从流文件读取数据。 
  fs.fsyncSync(file2.fd); 
  fs.closeSync(file2.fd); 
 
  formData.append('file', buf2); 
} catch (err) { 
  console.info('err:' + JSON.stringify(err)); 
} 
// 发送请求 
axios.post<string, AxiosResponse<string>, FormData>(this.uploadUrl, formData, { 
  headers: { 'Content-Type': 'multipart/form-data' }, 
  context: getContext(this), 
  onUploadProgress: (progressEvent: AxiosProgressEvent): void => { 
    console.info(progressEvent && progressEvent.loaded && progressEvent.total ? Math.ceil(progressEvent.loaded / progressEvent.total * 100) + '%' : '0%'); 
  }, 
}).then((res: AxiosResponse) => { 
  console.info("result" + JSON.stringify(res.data)); 
}).catch((error: AxiosError) => { 
  console.error("error:" + JSON.stringify(error)); 
})