Microsoft.DocAsCode.Build.Engine.XRefArchive.Open C# (CSharp) Method

        public static XRefArchive Open(string file, XRefArchiveMode mode)
        {
            if (file == null)
            {
                throw new ArgumentNullException(nameof(file));
            }
            FileStream fs = null;
            ZipArchive archive = null;
            try
            {
                bool isReadOnly = false;
                List<string> entries;
                switch (mode)
                {
                    case XRefArchiveMode.Read:
                        isReadOnly = true;
                        goto case XRefArchiveMode.Update;
                    case XRefArchiveMode.Update:
                        if (!File.Exists(file))
                        {
                            throw new FileNotFoundException($"File not found: {file}", file);
                        }
                        fs = File.Open(file, FileMode.Open, isReadOnly ? FileAccess.Read : FileAccess.ReadWrite);
                        archive = new ZipArchive(fs, isReadOnly ? ZipArchiveMode.Read : ZipArchiveMode.Update);
                        entries = (from entry in archive.Entries
                                   select entry.FullName).ToList();
                        entries.Sort(StringComparer.OrdinalIgnoreCase);
                        break;
                    case XRefArchiveMode.Create:
                        var directory = Path.GetDirectoryName(file);
                        if (!string.IsNullOrEmpty(directory))
                        {
                            Directory.CreateDirectory(directory);
                        }
                        fs = File.Create(file);
                        archive = new ZipArchive(fs, ZipArchiveMode.Update);
                        entries = new List<string>();
                        break;
                    default:
                        throw new ArgumentOutOfRangeException(nameof(mode));
                }
                return new XRefArchive(mode, archive, entries);
            }
            catch (Exception) when (fs != null)
            {
                if (archive != null)
                {
                    archive.Dispose();
                }
                fs.Close();
                throw;
            }
        }

 public async Task <bool> DownloadAsync(Uri uri, string outputFile)
 {
     if (uri == null)
     {
         throw new ArgumentNullException(nameof(uri));
     }
     if (!uri.IsAbsoluteUri)
     {
         throw new ArgumentException("Relative path is not allowed.", nameof(uri));
     }
     using (new LoggerPhaseScope(PhaseName))
         using (new LoggerFileScope(outputFile))
         {
             Logger.LogInfo($"Creating xref archive file...");
             try
             {
                 using (var xa = XRefArchive.Open(outputFile, XRefArchiveMode.Create))
                 {
                     await DownloadCoreAsync(uri, xa, true);
                 }
             }
             catch (Exception ex)
             {
                 Logger.LogError($"Unable to create archive: {ex.Message}");
                 return(false);
             }
             Logger.LogInfo($"Xref archive file created.");
             return(true);
         }
 }