提示用户保存路径？

Question

该功能使用包： https://github.com/flagbug/YoutubeExtractor

我想有这个功能提示针对要下载的文件保存路径的用户。

目前这是告诉我何时调用该函数： System.UnauthorizedAccessException：拒绝访问路径'C：\ Program Files（x86）\ IIS Express.mp4'。

protected void SaveVideo_Command(object sender, CommandEventArgs e) 
    { 
     var RowID = e.CommandArgument; 
     int submissionIDColumn = Convert.ToInt32(RowID); 
     var data = ParentSelect.DataKeys[submissionIDColumn]["SubmissionID"].ToString(); 
     int ParseDataInt = Convert.ToInt32(data); 
     var query = (from r in dbContext.Mains 
        where r.SubmissionID.Equals(ParseDataInt) 
        select r); 
     foreach (var record in query) 
     { 
      var VideoID = record.VideoUrl.FirstOrDefault(); 

      var link = "https://www.youtube.com/watch?v=5Mfb9gcB3lM"; 
      IEnumerable<VideoInfo> videoInfos = DownloadUrlResolver.GetDownloadUrls(link); 
      VideoInfo video = videoInfos.First(info => info.VideoType == VideoType.Mp4 && info.Resolution == 360); 

      if (video.RequiresDecryption) 
      { 
       DownloadUrlResolver.DecryptDownloadUrl(video); 
      } 
      string savePath = 
        Path.Combine(
         Environment.GetFolderPath(Environment.SpecialFolder.Desktop), 
         Path.ChangeExtension("myVideo", video.VideoExtension)); 
      var videoDownloader = new VideoDownloader(video, video.VideoExtension); 
      videoDownloader.Execute(); 
     } 
     dbContext.SaveChanges(); 
     LoadGrid(); 
    } 

Answer 1

我想得到的是我怎么能从用户那里得到一个“保存路径”。很明显，从用户那里获得本地文件结构的本地机器信息是一个安全漏洞，浏览器专门实现了防止这些信息被获取的功能。