public void HttpSendFileAsync(string fileName, Action <string> callBack) { Task.Factory.StartNew(() => { var fileUrl = string.Empty; try { using (var webClient = new WebClientUtil()) { fileUrl = Encoding.UTF8.GetString(webClient.UploadFile(Url, fileName)); callBack?.Invoke(fileUrl); } } catch (Exception ex) { _client.RaiseOnError(ex, "发送文件失败!"); } }); }