计算网络文件的大小
long CalculateFiles() { long totalsize = 0; bgWorker.ReportProgress((int)totalsize, UpProcessType.FileCalculate); foreach (UpdateInfo item in updateinfos) { try { HttpWebRequest webReq = (HttpWebRequest)WebRequest.Create(item.DownloadLink); HttpWebResponse webResp = (HttpWebResponse)webReq.GetResponse(); totalsize += webResp.ContentLength; webResp.Close(); } catch (Exception) { } } bgWorker.ReportProgress((int)totalsize, UpProcessType.FileCalculate); return totalsize; }