C-Sharp WPF EventHandler Warten und Erfassen

private void btn_Install_Click(object sender, RoutedEventArgs e)
{
}

public event EventHandler<EventArgs> ButtonClicked;
private static CancellationTokenSource ButtonClicked_CT_ = new CancellationTokenSource();

private void btn_Install_Click(object sender, RoutedEventArgs e)
{
    //...auslösen des Events
}


//Lösung A )
public static void StartServerAsync()
{
    ConnectServer();
    streamR_Server = new StreamReader(conServer);
    streamW_Server = new StreamWriter(conServer);

    Task.Factory.StartNew(() =>
    {
        conServer.WaitForConnection();
    	streamW_Server.WriteLine(AUTHENTICATION);
        streamW_Server.Flush();
        conServer.WaitForPipeDrain();

	string received = string.Empty;
        do
        {
            try
            {
                received = streamR_Server.ReadLine();
                        
	        **// HIER AUF BUTTON CLICK EVENT WARTEN !!!!**
                        
                streamW_Server.WriteLine(">>" + received);  
                streamW_Server.Flush();
                conServer.WaitForPipeDrain();
            }

	    catch (Exception ex) { }

        } while (conServer.IsConnected);
    });
}


// Lösung B )
private async void WaitForButtonClick()
{
    await Task.Factory.StartNew(()=>
    {
        while( !ButtonClicked_CT_.IsCancellationRequested)
        {
            **// HIER AUF BUTTON CLICK EVENT WARTEN  !!!!**
            if(ButtonClicked) {  ButtonClicked_CT_.Cancel;}
            Thread.Sleep(200);
        }
    });
}