HarmonyOS 鸿蒙Next：保存线上PDF至文件管理download目录后无法查看问题 HarmonyOS 鸿蒙Next：首次保存线上PDF至download目录可查看，多次保存后文档无法打开，WPS提示格式错误或内容损坏

HarmonyOS 鸿蒙Next：保存线上PDF至文件管理download目录后无法查看问题
HarmonyOS 鸿蒙Next：首次保存线上PDF至download目录可查看，多次保存后文档无法打开，WPS提示格式错误或内容损坏

import { fileIo, fileUri, picker } from '@kit.CoreFileKit';
import { BusinessError, request } from '@kit.BasicServicesKit';
import { promptAction } from '@kit.ArkUI';
import { webview } from '@kit.ArkWeb';
import { JSON } from '@kit.ArkTS';

@Entry
@Component
struct indexPage {

  webContorller: WebviewController = new webview.WebviewController()
  fileSrc = "https://www.gov.cn/zhengce/pdfFile/2023_PDF.pdf"

  build() {
    Column({ space: 10 }) {
      Scroll() {
        Web({ src: this.fileSrc, controller: this.webContorller })
          .domStorageAccess(true)
      }.layoutWeight(1)

      Button('保存到本机目录').onClick(() => {
        let fileAddr = this.fileSrc.split('//')[1]
        let fileName = fileAddr.split('/')[fileAddr.split('/').length - 1]

        if (fileIo.accessSync(getContext(this).cacheDir + '/' + fileName)) {
          fileIo.unlinkSync(getContext(this).cacheDir + '/' + fileName)
        }
        // 文件下载到应用沙箱
        request.downloadFile(getContext(this),
          { url: this.fileSrc, filePath: getContext(this).cacheDir + '/' + fileName }, (err, res) => {
            res.on('fail', (reject) => {
              console.log('文件下载 下载失败 --' + reject)
            })
            res.on('progress', (resolve) => {
              console.log('文件下载 下载成功 --' + resolve)
            })
          })

        let documentOptions = new picker.DocumentSaveOptions()
        documentOptions.pickerMode = picker.DocumentPickerMode.DOWNLOAD

        let documentPicker = new picker.DocumentViewPicker()

        try {
          documentPicker.save(documentOptions, (err: BusinessError, DocumentSaveResult: Array<string>) => {
            DocumentSaveResult.forEach(uri => {
              console.log('文件下载 uri ' + JSON.stringify(uri))

              let file = fileIo.openSync(getContext(this).cacheDir + '/' + fileName,
                fileIo.OpenMode.READ_WRITE | fileIo.OpenMode.CREATE);
              console.log('文件下载 file地址 ---' + getContext(this).cacheDir + '/' + fileName)
              let path: string = new fileUri.FileUri(uri).path
              if (fileIo.accessSync(path + '/' + file.name)) {
                fileIo.unlinkSync(path + '/' + file.name)
              }
              console.log('文件下载 file2地址--- ' + path + '/' + file.name)
              let file2 = fileIo.openSync(path + '/' + file.name, fileIo.OpenMode.READ_WRITE | fileIo.OpenMode.CREATE)
              console.log('文件下载 文件管理存在' + fileIo.accessSync(path + '/' + file.name))
              fileIo.copyFileSync(file.fd, file2.fd)
              fileIo.closeSync(file2);
              fileIo.closeSync(file);
              promptAction.showToast({
                message: '保存成功'
              })
            })
          })
        } catch (err) {
          console.log('文件下载 报错 ' + JSON.stringify(err))
        }
      })
    }
    .width('100%')
    .height('100%')
  }
}