private void main()
{
BackgroundWorker bw = new BackgroundWorker();
bw.WorkerSupportsCancellation = true;
bw.WorkerReportsProgress = true;
bw.DoWork += new DoWorkEventHandler(bw_DoWork);
bw.RunWorkerCompleted += new RunWorkerCompletedEventHandler(bw_RunWorkerCompleted);
info_display.AppendText(Environment.NewLine + "正在发送请求……" + Environment.NewLine);
info_display.ScrollToCaret();
bw.RunWorkerAsync();
}