CASCExplorer.CDNIndexHandler.DownloadIndexFile C# (CSharp) Method

        private void DownloadIndexFile(string archive, int i)
        {
            try
            {
                string file = config.CDNPath + "/data/" + archive.Substring(0, 2) + "/" + archive.Substring(2, 2) + "/" + archive + ".index";
                string url = "http://" + config.CDNHost + "/" + file;

                Stream stream = Cache.OpenFile(file, url, false);

                if (stream != null)
                {
                    ParseIndex(stream, i);
                }
                else
                {
                    using (var fs = downloader.OpenFile(url))
                        ParseIndex(fs, i);
                }
            }
            catch
            {
                throw new Exception("DownloadFile failed!");
            }
        }

        public static CDNIndexHandler Initialize(CASCConfig config, BackgroundWorkerEx worker)
        {
            var handler = new CDNIndexHandler(config, worker);

            worker?.ReportProgress(0, "Loading \"CDN indexes\"...");

            for (int i = 0; i < config.Archives.Count; i++)
            {
                string archive = config.Archives[i];

                if (config.OnlineMode)
                    handler.DownloadIndexFile(archive, i);
                else
                    handler.OpenIndexFile(archive, i);

                worker?.ReportProgress((int)((i + 1) / (float)config.Archives.Count * 100));
            }

            return handler;
        }