How do I know when the ThreadPool is done?
Can someone help me? Thanks

private void Ping()
{
    foreach (var lista in dati)
    {
            ThreadPool.QueueUserWorkItem(lista.pingClasse);
    }
}

public void pingClasse(Object state)
{
    try
    {
        Ping ping = new Ping();
        PingReply reply = ping.Send(Ip);
        if (reply.Status == IPStatus.Success)
        {
            TempoPing = Convert.ToString(reply.RoundtripTime + " ms");
            StatoDatagrid = 2;
            StatoLista = "Success";
        }
        else
        {
            StatoDatagrid = 1;
            StatoLista = "Failed";
        }
    }
    catch (ArgumentOutOfRangeException)
    {

    }
}

My problem is how do I know when the ThreadPool is done?