title: List used TCP port using C#
body: <p>This is the answer to my questions.</p>
  
  <p>How to list binded/used TCP port in C#. Used modified code from <a href="https://stackoverflow.com/questions/570098/in-c-how-to-check-if-a-tcp-port-is-available/570461#570461">jro</a> </p>
  
  <pre><code>        static void ListUsedTCPPort(ref ArrayList usedPort)
      {
          IPGlobalProperties ipGlobalProperties = IPGlobalProperties.GetIPGlobalProperties();
          IPEndPoint[] tcpConnInfoArray = ipGlobalProperties.GetActiveTcpListeners();
          IEnumerator myEnum = tcpConnInfoArray.GetEnumerator();
  
          while (myEnum.MoveNext())
          {
              IPEndPoint TCPInfo = (IPEndPoint)myEnum.Current;
              usedPort.Add(TCPInfo.Port);
          }
      }
  </code></pre>
  
  <p><strong>Original questions.</strong>
  This is how i list TCP port using C#. It is modified code i found in this forum(forgot exactly where i got it. If you are the original developer, notify me and ill put credits where due.)</p>
  
  <pre><code>    //List used tcp port
      static void ListUsedTCPPort(ref ArrayList usedPort)
      {
          IPGlobalProperties ipGlobalProperties = IPGlobalProperties.GetIPGlobalProperties();
          TcpConnectionInformation[] tcpConnInfoArray = ipGlobalProperties.GetActiveTcpConnections();
          IEnumerator myEnum = tcpConnInfoArray.GetEnumerator();
  
          while (myEnum.MoveNext())
          {
              TcpConnectionInformation TCPInfo = (TcpConnectionInformation)myEnum.Current;
              usedPort.Add(TCPInfo.LocalEndPoint.Port);
          }
      }
  </code></pre>
  
  <p>Problem is, the results is different from used tcp port listed in TCPview(Protocol-TCP, Local port).
  By the way, i do know that this list used TCP port at the EXACT time its called. 
  What did i did wrong?</p>