public partial class ThreadTest : System.Web.UI.Page
{
    public static int Counter = 0;
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            Counter = 0;
            Timer1.Enabled = false;
        }
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        Timer1.Enabled = true;
        DateTime dtStart = DateTime.Now;

        NewThreadWork newThreadWork = new NewThreadWork();
        newThreadWork.ThreadStart += new System.Threading.ThreadStart(LongTimeOpt);
        newThreadWork.Run();

        TimeSpan ts = DateTime.Now - dtStart;
        this.TextBox1.Text = ts.Milliseconds.ToString();
    }

    private void LongTimeOpt()
    {
        int totle = 100000000;
        for (int i = 0; i < totle; i++)
        {
            for (int j = 0; j < totle; j++)
                Counter = i;
        }
    }

  
    protected void Button2_Click(object sender, EventArgs e)
    {
        this.TextBox2.Text = Counter.ToString();
    }

    public class NewThreadWork
    {
        private static object obj = new object();
        public System.Threading.ThreadStart ThreadStart;

        public void Run()
        {
            lock (obj)
            {
                System.Threading.Thread thread = new System.Threading.Thread(ThreadStart);
                thread.Start();
            }
        }
    }
    protected void Timer1_Tick(object sender, EventArgs e)
    {
        this.TextBox2.Text = Counter.ToString();
    }
}