多线程 + Ping        Ping pingSender = new Ping();
        PingOptions options = new PingOptions();
        options.DontFragment = true;
        string data = "xx";
        byte[] buffer = Encoding.ASCII.GetBytes(data);
        PingReply reply = pingSender.Send(Dns.GetHostAddresses("网址")[0], 120, buffer, options);
        if (reply.Status == IPStatus.Success)
        {
            this.roundtripTime = reply.RoundtripTime; //连接时间
        }