HarmonyOS 鸿蒙Next request.downloadFile 报错 13400001

13400001 是指文件操作异常 ，参考地址：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/errorcode-request-V5#section13400001-%E6%96%87%E4%BB%B6%E6%93%8D%E4%BD%9C%E5%BC%82%E5%B8%B8

需要添加网络权限：ohos.permission.INTERNET

在调用request.downloadFile方法时，需确保提供的filePath参数是一个完整的文件路径，所有父级路径都已创建，以避免下载失败。 沙箱文件目录创建请参考链接：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/js-apis-file-fs-V5#fsmkdir11

可以参考以下demo:

import common from '@ohos.app.ability.common';

import request from '@ohos.request';

import { BusinessError } from '@ohos.base';

import { fileIo as fs } from '@kit.CoreFileKit'; // 获取应用文件路径

import { webview } from '@kit.ArkWeb';

let context = this as common.UIAbilityContext;

let filesDir = context.filesDir;

@Entry
@Component
export struct Index {

  @State message: string = 'Hello World';

  @State picUrl: string =
    'https://developer.huawei.com/allianceCmsResource/resource/HUAWEI_Developer_VUE/images/bannerpc12.jpg';

  private webviewController: WebviewController = new webview.WebviewController();

  build() {
    Row() {
      Scroll() {
        Column() {
          Button('创建路径').onClick(() => {
            let dirPath = filesDir + "/testDir1/testDir2/testDir3";
            fs.mkdir(dirPath, true).then(() => {
              console.info("mkdir succeed");
            }).catch((err: BusinessError) => {
              console.error("mkdir failed with error message: " + err.message + ", error code: " + err.code);
            });
          })
          Button('下载').onClick(() => {
            try {
              //下载文件
              request.downloadFile(context,
                { url: this.picUrl, filePath: filesDir + "/testDir1/testDir2/testDir3" + '/ceshi.png' })
                .then((downloadTask: request.DownloadTask) => {
                  let failCallback = (err: number) => {
                    console.error(`Failed to download the task. Code: ${err}`);
                  };
                  downloadTask.on('fail',
                    failCallback);
                  //开启回调
                  downloadTask.on('complete', () => {
                    console.info('downloadTask1 complete====');
                  })
                  downloadTask.off('fail');
                }).catch((err: BusinessError) => {
                  console.error(`Invoke downloadTask failed-----, code is ${err.code}, message is ${err.message}`);
                });
            } catch (error) {
              let err: BusinessError = error as BusinessError;
              console.error(`Invoke downloadTask downloadFile failed====, code is ${err.code}, message is ${err.message}`);
            }
          }).width('100%')
        }
      }.height('100%')
    }
  }
}