MonitoringNetwork.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Drawing;
using System.Linq;
using System.Net;
using System.Net.NetworkInformation;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace NetworkMonitor.WinForm
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            InitializeDataGridView();
            LoadConnections();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void InitializeDataGridView()
        {
            dgvConnections.ColumnCount = 6;
            dgvConnections.Columns[0].Name = "PID";
            dgvConnections.Columns[1].Name = "Programa";
            dgvConnections.Columns[2].Name = "Local Address";
            dgvConnections.Columns[3].Name = "Local Port";
            dgvConnections.Columns[4].Name = "Remote Address";
            dgvConnections.Columns[5].Name = "Remote Port";
        }

        private void LoadConnections()
        {
            dgvConnections.Rows.Clear();

            var connections = IPGlobalProperties.GetIPGlobalProperties().GetActiveTcpConnections();

            foreach (var conn in connections)
            {
                string localAddress = conn.LocalEndPoint.Address.ToString();
                int localPort = conn.LocalEndPoint.Port;
                string remoteAddress = conn.RemoteEndPoint.Address.ToString();
                int remotePort = conn.RemoteEndPoint.Port;
                int pid = GetProcessId(conn);
                string processName = GetProcessName(pid);

                dgvConnections.Rows.Add(pid, processName, localAddress, localPort, remoteAddress, remotePort);
            }
        }

        private int GetProcessId(TcpConnectionInformation conn)
        {
            try
            {
                var tcpTable = new MIB_TCPROW_OWNER_PID[1];
                int bufferSize = 0;
                GetExtendedTcpTable(IntPtr.Zero, ref bufferSize, false, 2, TCP_TABLE_CLASS.TCP_TABLE_OWNER_PID_ALL, 0);
                IntPtr tcpTablePtr = Marshal.AllocHGlobal(bufferSize);

                try
                {
                    if (GetExtendedTcpTable(tcpTablePtr, ref bufferSize, false, 2, TCP_TABLE_CLASS.TCP_TABLE_OWNER_PID_ALL, 0) == 0)
                    {
                        int rowSize = Marshal.SizeOf(typeof(MIB_TCPROW_OWNER_PID));
                        int count = Marshal.ReadInt32(tcpTablePtr);
                        IntPtr rowPtr = new IntPtr(tcpTablePtr.ToInt64() + 4);

                        for (int i = 0; i < count; i++)
                        {
                            MIB_TCPROW_OWNER_PID row = Marshal.PtrToStructure<MIB_TCPROW_OWNER_PID>(rowPtr);
                            if (row.localAddr == BitConverter.ToUInt32(conn.LocalEndPoint.Address.GetAddressBytes(), 0) &&
                                row.localPort == (ushort)IPAddress.HostToNetworkOrder((short)conn.LocalEndPoint.Port) &&
                                row.remoteAddr == BitConverter.ToUInt32(conn.RemoteEndPoint.Address.GetAddressBytes(), 0) &&
                                row.remotePort == (ushort)IPAddress.HostToNetworkOrder((short)conn.RemoteEndPoint.Port))
                            {
                                return Convert.ToInt32(row.owningPid);
                            }
                            rowPtr = new IntPtr(rowPtr.ToInt64() + rowSize);
                        }
                    }
                }
                finally
                {
                    Marshal.FreeHGlobal(tcpTablePtr);
                }
            }
            catch
            {
                return -1;
            }
            return -1;
        }

        private string GetProcessName(int pid)
        {
            try
            {
                return Process.GetProcessById(pid).ProcessName;
            }
            catch
            {
                return "Desconhecido";
            }
        }

        internal enum TCP_TABLE_CLASS
        {
            TCP_TABLE_BASIC_LISTENER,
            TCP_TABLE_BASIC_CONNECTIONS,
            TCP_TABLE_BASIC_ALL,
            TCP_TABLE_OWNER_PID_LISTENER,
            TCP_TABLE_OWNER_PID_CONNECTIONS,
            TCP_TABLE_OWNER_PID_ALL,
            TCP_TABLE_OWNER_MODULE_LISTENER,
            TCP_TABLE_OWNER_MODULE_CONNECTIONS,
            TCP_TABLE_OWNER_MODULE_ALL
        }

        [StructLayout(LayoutKind.Sequential)]
        internal struct MIB_TCPROW_OWNER_PID
        {
            public uint state;
            public uint localAddr;
            public ushort localPort;
            public uint remoteAddr;
            public ushort remotePort;
            public uint owningPid;
        }

        [DllImport("iphlpapi.dll", SetLastError = true)]
        private static extern int GetExtendedTcpTable(IntPtr pTcpTable, ref int dwSize, bool sort, int ipVersion, TCP_TABLE_CLASS tblClass, uint reserved = 0);

        private void RefreshButton_Click(object sender, EventArgs e)
        {
            LoadConnections();
        }
    }
}