IPHlpAPI32.cs

using System;
using System.Net;
using System.Collections;
using System.Runtime.InteropServices;
using System.Text;

namespace IpHlpApidotnet
{
	#region UDP

    [StructLayout(LayoutKind.Sequential)]
    public struct MIB_UDPROW_OWNER_PID
    {
        public IPEndPoint Local;
        public int dwOwningPid;
        public string ProcessName;
    }

    public struct MIB_UDPROW_OWNER_MODULE
    {
        public IPEndPoint Local;
        public uint dwOwningPid;
        public long liCreateTimestamp; //LARGE_INTEGER
        /*union {
            struct {
                DWORD   SpecificPortBind : 1;
            };
            DWORD       dwFlags;
        };*/
        public ulong[] OwningModuleInfo; //size TCPIP_OWNING_MODULE_SIZE
    }

    public struct MIB_UDPTABLE_OWNER_PID
    {
        public int dwNumEntries;
        public MIB_UDPROW_OWNER_PID[] table;
    }

    public struct _MIB_UDPTABLE_OWNER_MODULE
    {
        public uint dwNumEntries;
        public MIB_UDPROW_OWNER_MODULE[] table;
    }

    public enum UDP_TABLE_CLASS
    {
        UDP_TABLE_BASIC, //A MIB_UDPTABLE table that contains all UDP endpoints on the machine is returned to the caller.
        UDP_TABLE_OWNER_PID, //A MIB_UDPTABLE_OWNER_PID or MIB_UDP6TABLE_OWNER_PID that contains all UDP endpoints on the machine is returned to the caller.
        UDP_TABLE_OWNER_MODULE //A MIB_UDPTABLE_OWNER_MODULE or MIB_UDP6TABLE_OWNER_MODULE that contains all UDP endpoints on the machine is returned to the caller.
    }

	public struct MIB_UDPSTATS
	{
		public int dwInDatagrams ;
		public int dwNoPorts ;
		public int dwInErrors ;
		public int dwOutDatagrams ;
		public int dwNumAddrs;
	}

	public struct MIB_UDPTABLE 
	{
		public int dwNumEntries;  
		public MIB_UDPROW[] table;
	}

	public struct MIB_UDPROW 
	{
		public IPEndPoint Local;
	}

	public struct MIB_EXUDPTABLE
	{
		public int dwNumEntries;  
		public MIB_EXUDPROW[] table;

	}

	public struct MIB_EXUDPROW
	{
		public IPEndPoint Local;  
		public int dwProcessId;
		public string ProcessName;
	}

	#endregion

	#region TCP
    [StructLayout(LayoutKind.Sequential)]
    public struct MIB_TCPTABLE_OWNER_MODULE
    {
        public uint dwNumEntries;
        public MIB_TCPROW_OWNER_MODULE[] table;
    }

    public struct MIB_TCPROW_OWNER_MODULE
    {
        public const int TCPIP_OWNING_MODULE_SIZE = 16;
        public uint dwState;
        public IPEndPoint Local; //LocalAddress
        public IPEndPoint Remote; //RemoteAddress
        public uint dwOwningPid;
        public uint liCreateTimestamp; //LARGE_INTEGER
        public ulong[] OwningModuleInfo; //Look how to define array size in structure ULONGLONG   = new ulong[TCPIP_OWNING_MODULE_SIZE]     
    }

    public struct MIB_TCPTABLE_OWNER_PID
    {
        public int dwNumEntries;
        public MIB_TCPROW_OWNER_PID[] table;
    }

    public struct MIB_TCPROW_OWNER_PID
    {
        public int dwState;
        public IPEndPoint Local; //LocalAddress
        public IPEndPoint Remote; //RemoteAddress
        public int dwOwningPid;
        public string State;
        public string ProcessName;
    }

    public 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,
    }

	public struct MIB_TCPSTATS
	{
		public int dwRtoAlgorithm ;
		public int dwRtoMin ;
		public int dwRtoMax ;
		public int dwMaxConn ;
		public int dwActiveOpens ;
		public int dwPassiveOpens ;
		public int dwAttemptFails ;
		public int dwEstabResets ;
		public int dwCurrEstab ;
		public int dwInSegs ;
		public int dwOutSegs ;
		public int dwRetransSegs ;
		public int dwInErrs ;
		public int dwOutRsts ;
		public int dwNumConns ;
	}

	public struct MIB_TCPTABLE 
	{
		public int dwNumEntries;  
		public MIB_TCPROW[] table;
	}

	public struct MIB_TCPROW 
	{
		public string StrgState; 
		public int iState;
		public IPEndPoint Local;  
		public IPEndPoint Remote;
	}

	public struct MIB_EXTCPTABLE
	{
		public int dwNumEntries;  
		public MIB_EXTCPROW[] table;

	}

	public struct MIB_EXTCPROW
	{
		public string StrgState;
		public int iState;
		public IPEndPoint Local;  
		public IPEndPoint Remote;
		public int dwProcessId;
		public string ProcessName;
	}
	#endregion

	
	public class IPHlpAPI32Wrapper
	{
		public const byte NO_ERROR  = 0;
		public const int FORMAT_MESSAGE_ALLOCATE_BUFFER = 0x00000100;
		public const int FORMAT_MESSAGE_IGNORE_INSERTS = 0x00000200;
		public const int FORMAT_MESSAGE_FROM_SYSTEM  = 0x00001000;
		public int dwFlags = FORMAT_MESSAGE_ALLOCATE_BUFFER | 
			FORMAT_MESSAGE_FROM_SYSTEM | 
			FORMAT_MESSAGE_IGNORE_INSERTS;

		[DllImport("iphlpapi.dll",SetLastError=true)]
		public extern static int GetUdpStatistics (ref MIB_UDPSTATS pStats );

		[DllImport("iphlpapi.dll",SetLastError=true)]
		public static extern int GetUdpTable(byte[] UcpTable, out int pdwSize, bool bOrder);

		[DllImport("iphlpapi.dll",SetLastError=true)]
		public extern static int GetTcpStatistics (ref MIB_TCPSTATS pStats );

		[DllImport("iphlpapi.dll",SetLastError=true)]
		public static extern int GetTcpTable(byte[] pTcpTable, out int pdwSize, bool bOrder);

		[DllImport("iphlpapi.dll",SetLastError=true)]
		public extern static int AllocateAndGetTcpExTableFromStack(ref IntPtr pTable, bool bOrder, IntPtr heap ,int zero,int flags );

		[DllImport("iphlpapi.dll",SetLastError=true)]
		public extern static int AllocateAndGetUdpExTableFromStack(ref IntPtr pTable, bool bOrder, IntPtr heap,int zero,int flags );

		[ DllImport( "kernel32" ,SetLastError=true)]
		public static extern IntPtr GetProcessHeap(); 

		[ DllImport( "kernel32" ,SetLastError=true)]
		private static extern int FormatMessage( int flags, IntPtr source, int messageId,
			int languageId, StringBuilder buffer, int size, IntPtr arguments ); 

		[DllImport("iphlpapi.dll", SetLastError=true)]
        public static extern int GetExtendedTcpTable(byte[] pTcpTable, out int dwOutBufLen, bool sort, 
            int ipVersion, TCP_TABLE_CLASS tblClass, int reserved);

		[DllImport("iphlpapi.dll", SetLastError=true)]
        public static extern int GetExtendedUdpTable(byte[] pUdpTable, out int dwOutBufLen, bool sort, 
            int ipVersion, UDP_TABLE_CLASS tblClass, int reserved);

        public static string GetAPIErrorMessageDescription(int ApiErrNumber ) 
		{
			System.Text.StringBuilder sError = new System.Text.StringBuilder(512); 
			int lErrorMessageLength; 
			lErrorMessageLength = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM,(IntPtr)0, ApiErrNumber, 0, sError, sError.Capacity, (IntPtr)0) ;
			
			if(lErrorMessageLength > 0)
			{ 
				string strgError = sError.ToString();
				strgError=strgError.Substring(0,strgError.Length-2);
				return strgError+" ("+ApiErrNumber.ToString()+")";
			}
			return "none";
		}
	}
}