ios - 从 Alamofire 下载请求访问文件

Question

因此，我使用 Alamofire 和此请求发出了下载请求并返回图像、语音、视频，我能够destinationURL通过image back 如何将它添加到 ImageView 等等现在，我还担心每次打开页面时都会调用这个函数，即使文件是在文档中下载的，这不是会丢失内存吗？并影响性能？？

        let destination = DownloadRequest.suggestedDownloadDestination(for: .documentDirectory)
        Alamofire.download(
            "url",
            method: .get,
            parameters: nil,
            encoding: JSONEncoding.default,
            headers:nil ,
            to: destination).downloadProgress(closure: { (progress) in
                //progress closure
            }).response(completionHandler: { (DefaultDownloadResponse) in
                //here you able to access the DefaultDownloadResponse
                //result closure
                print("*****DefaultDownloadResponse***** \(DefaultDownloadResponse.response) and \(DefaultDownloadResponse.resumeData) and \(DefaultDownloadResponse.destinationURL)")
            })

Answer 1

您必须这样做才能显示下载的文件！
你可以这样：

extension ViewPreRegistrationViewController : UIDocumentInteractionControllerDelegate {


  func startDownload(Url:String) -> Void {
    headers = ["Authorization": "Token \(Auth.userToken!)"]
    let destination = DownloadRequest.suggestedDownloadDestination(for: .documentDirectory)
    Alamofire.download(
      Url,
      method: .get,
      encoding: JSONEncoding.default,
      headers: headers,
      to: destination).downloadProgress(closure: { (progress) in
        //progress closure
      }).response(completionHandler: { (DefaultDownloadResponse) in
        //here you able to access the DefaultDownloadResponse
        let docController = UIDocumentInteractionController(url: DefaultDownloadResponse.destinationURL!)
        docController.delegate = self
        docController.name = "show"
        docController.presentPreview(animated: true)
        //result closure
      })
  }



  func documentInteractionControllerViewControllerForPreview(_ controller: UIDocumentInteractionController) -> UIViewController {
    return self
  }


}

并使用：

  @IBAction func exportPdfButton(_ sender: Any) {
    let fullURL = "your url"
    startDownload(Url: fullURL)
  }