HarmonyOS fileAccess使用

//获取选择文件的沙箱路径 
async function example():Promise<string|undefined> { 
  try { 
    let PhotoSelectOptions = new picker.PhotoSelectOptions();//图片选项 
    let DocumentSelectOptions = new picker.DocumentSelectOptions();//文件选项 
    // PhotoSelectOptions.MIMEType = picker.PhotoViewMIMETypes.IMAGE_TYPE; 
    // PhotoSelectOptions.maxSelectNumber = 5; 
    let photoPicker = new picker.PhotoViewPicker();//图片 
    let DocumentViewPicker = new picker.DocumentViewPicker();//文件 
    let docs = await photoPicker.select(PhotoSelectOptions); 
    console.info('PhotoViewPicker.select successfully, PhotoSelectResult uri: ’ + JSON.stringify(docs)); 
    fs.openSync(docs.photoUris[0],fs.OpenMode.READ_ONLY);//只能只读打开 
    console.info(‘PhotoViewPicker openSync success’); 
    return docs.photoUris[0]; 
  } catch (err) { 
    console.error('PhotoViewPicker failed with err: ’ + err); 
    return “null” 
  } 
}