AJAX Progress Bar for ASP.NET

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Threading;
using hmlib.Web.UI.Controls;

namespace WebTest.ProgressBarTest
{
	public partial class ucStartOnServerSide : System.Web.UI.UserControl
	{
		protected void Page_Load(object sender, EventArgs e)
		{
			if (IsPostBack) return;
			this.ProgressBar1.ProgressId = "TestProgress";
		}
		protected void btnStart_Click(object sender, EventArgs e)
		{
			btnStart.Enabled = false;
			rbSpeed.Enabled = false;
			int interval = int.Parse(rbSpeed.SelectedValue);
			Thread thread = new Thread(() => this.StartProgress(ProgressBar1.Progress, interval));
			thread.Start();
		}
		private void StartProgress(Progress progress, int interval)
		{
			int rounds = int.Parse(rbRounds.SelectedValue);
			for (int i = 0; i < rounds; i++)
			{
				progress.SetProgress(0);
				progress.AddMessageLine("Round " + (i + 1) + " started");
				for (int j = 0; j < 100; j++)
				{
					//interval = Math.Max(10, interval - 1);
					double value = .98 * j / 100d;
					progress.SetProgress(value);
					//progress.AddMessageLine(value.ToString());
					Thread.Sleep(interval);
				}
			}
			progress.AddMessageLine("Finished");
			progress.SetProgress(1);
		}
	}
}