调用GetRequestStream（）会将WPF UI挂起1秒

Question

我创建了一个wpf应用程序，它控制一个标签和两个用于启动和停止计时器的按钮。

我创建了两个DispatcherTimers，一个计时器将在每50毫秒后触发一次，并用计数值更新标签。另一个DispatcherTimer将在每2秒后触发一次，它将数据发布到名为“http://posttestserver.com/post.php?dir=Test”的HTTP后测试服务器。在这个计时器中，我使用GetRequestStream，导致UI停止1秒但我的数据发布到posttestserver。 我使用了以下代码。

public partial class MainWindow：Window     {

    static int count = 0;
    DispatcherTimer dispatchtimer = null;
    DispatcherTimer WebDispatchTimer = null;
    public MainWindow()
    {
        InitializeComponent();
        dispatchtimer = new DispatcherTimer();
        WebDispatchTimer = new DispatcherTimer();
        WebDispatchTimer.Interval = TimeSpan.FromMilliseconds(2000);
        dispatchtimer.Interval = TimeSpan.FromMilliseconds(50);
        dispatchtimer.Tick += new EventHandler(dispatchtimer_Tick);
        WebDispatchTimer.Tick += new EventHandler(senddata_Tick);
    }

    private void button1_Click(object sender, RoutedEventArgs e)
    {
        WebDispatchTimer.Start();
        dispatchtimer.Start();
    }
    private void dispatchtimer_Tick(Object sender, EventArgs args)
    {
        count += 1;
        label1.Content = count.ToString();
    }
    private void senddata_Tick(Object sender, EventArgs args)
    {
        string postdata = "This is a test that posts this string to a Web server\n";
        try
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://posttestserver.com/post.php?dir=abcd");
            request.Method = "POST";
            request.ProtocolVersion = HttpVersion.Version11;
            byte[] byteArray = Encoding.UTF8.GetBytes(postdata);
            request.ContentType = "application/x-www-form-urlencoded";
            request.ContentLength = byteArray.Length;
            request.Proxy = null;
            using (Stream dataStream = request.GetRequestStream())
            {
                dataStream.Write(byteArray, 0, byteArray.Length);
                dataStream.Flush();
                dataStream.Close();
            }
            var response = request.GetResponse() as HttpWebResponse;
            response.Close();
            request.Abort();
            request = null;
        }
        catch (WebException ex)
        {
            MessageBox.Show(ex.Message);
            WebDispatchTimer.Stop();

        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
            WebDispatchTimer.Stop();
        }         
    }
    private void button2_Click(object sender, RoutedEventArgs e)
    {
        WebDispatchTimer.Stop();
        dispatchtimer.Stop();
    }
}

我不希望我的UI挂起1秒钟。哪里弄错了？帮助我。