C#如何检测网络端口连接的状态

C#如何检测/监控远程连接网络端口的情况（例如：3389端口是否处于监听状态，是否建立了连接等）。

using System;
using System.Collections.Generic;
using System.Text;
using System.Net.NetworkInformation;

namespace test
{
    class Program
    {

        static void Main(string[] args)
        {
            GetTcpConnections();
        }

        public static void GetTcpConnections()
        {
            IPGlobalProperties properties = IPGlobalProperties.GetIPGlobalProperties();
      
            TcpConnectionInformation[] connections = properties.GetActiveTcpConnections();
            foreach (TcpConnectionInformation t in connections)
            {
                Console.Write("Local endpoint: {0} ", t.LocalEndPoint.ToString());
                Console.Write("Remote endpoint: {0} ", t.RemoteEndPoint.ToString());
                Console.WriteLine("{0}", t.State);
            }
            Console.WriteLine();
            Console.ReadLine();
        }

    }
}

运行结果：

Local endpoint: 127.0.0.1:1025 Remote endpoint: 127.0.0.1:1026 Established
Local endpoint: 127.0.0.1:1026 Remote endpoint: 127.0.0.1:1025 Established
Local endpoint: 127.0.0.1:1028 Remote endpoint: 127.0.0.1:16992 CloseWait
Local endpoint: 127.0.0.1:1110 Remote endpoint: 127.0.0.1:4900 Established
Local endpoint: 127.0.0.1:2754 Remote endpoint: 127.0.0.1:1110 CloseWait
Local endpoint: 127.0.0.1:2762 Remote endpoint: 127.0.0.1:1110 CloseWait
Local endpoint: 127.0.0.1:2773 Remote endpoint: 127.0.0.1:1110 CloseWait
Local endpoint: 127.0.0.1:2913 Remote endpoint: 127.0.0.1:1110 CloseWait
Local endpoint: 127.0.0.1:3014 Remote endpoint: 127.0.0.1:1110 CloseWait
Local endpoint: 127.0.0.1:3531 Remote endpoint: 127.0.0.1:1110 CloseWait
Local endpoint: 127.0.0.1:4012 Remote endpoint: 127.0.0.1:1110 CloseWait
Local endpoint: 127.0.0.1:4900 Remote endpoint: 127.0.0.1:1110 Established