C# Oid.IsRootOf方法代码示例

        /// <summary>
        /// Walks an SNMP mib table displaying the results on the fly (unless otherwise desired)
        /// </summary>
        /// <param name="log_options">Logging options</param>
        /// <param name="ip">IPAddress of device to walk</param>
        /// <param name="in_community">Read-community of device to walk</param>
        /// <param name="start_oid">Start OID (1.3, etc)</param>
        /// <returns></returns>
        public static List<SnmpV1Packet> MibWalk(LOG_OPTIONS log_options, IPAddress ip, string in_community, string start_oid)
        {
            stop = false;
            List<SnmpV1Packet> packets = new List<SnmpV1Packet>();
            // SNMP community name
            OctetString community = new OctetString(in_community);

            // Define agent parameters class
            AgentParameters param = new AgentParameters(community);
            // Set SNMP version to 1
            param.Version = SnmpVersion.Ver1;

            // Construct target
            UdpTarget target = new UdpTarget(ip, 161, 2000, 1);

            // Define Oid that is the root of the MIB
            //  tree you wish to retrieve
            Oid rootOid = new Oid(start_oid); // ifDescr

            // This Oid represents last Oid returned by
            //  the SNMP agent
            Oid lastOid = (Oid)rootOid.Clone();

            // Pdu class used for all requests
            Pdu pdu = new Pdu(PduType.GetNext);

            // Loop through results
            while (lastOid != null)
            {
                // When Pdu class is first constructed, RequestId is set to a random value
                // that needs to be incremented on subsequent requests made using the
                // same instance of the Pdu class.
                if (pdu.RequestId != 0)
                {
                    pdu.RequestId += 1;
                }
                if (stop)
                {
                    return packets;
                }
                // Clear Oids from the Pdu class.
                pdu.VbList.Clear();
                // Initialize request PDU with the last retrieved Oid
                pdu.VbList.Add(lastOid);
                // Make SNMP request
                SnmpV1Packet result = (SnmpV1Packet)target.Request(pdu, param);
                // You should catch exceptions in the Request if using in real application.

                // If result is null then agent didn't reply or we couldn't parse the reply.
                if (result != null)
                {
                    // ErrorStatus other then 0 is an error returned by
                    // the Agent - see SnmpConstants for error definitions
                    packets.Add(result);
                    if (result.Pdu.ErrorStatus != 0)
                    {
                        // agent reported an error with the request
                        Logger.Write(log_options, module, "Error in SNMP reply. Error " + result.Pdu.ErrorStatus + " index " + result.Pdu.ErrorIndex);
                        lastOid = null;
                        break;
                    }
                    else
                    {
                        // Walk through returned variable bindings
                        foreach (Vb v in result.Pdu.VbList)
                        {
                            // Check that retrieved Oid is "child" of the root OID
                            if (rootOid.IsRootOf(v.Oid))
                            {
                                Logger.Write(log_options, module, v.Oid.ToString() + " " + SnmpConstants.GetTypeName(v.Value.Type) + ": " + v.Value.ToString());
                                lastOid = v.Oid;
                            }
                            else
                            {
                                // we have reached the end of the requested
                                // MIB tree. Set lastOid to null and exit loop
                                lastOid = null;
                            }
                        }
                    }
                }
                else
                {
                    Console.WriteLine("No response received from SNMP agent.");
                }
            }
            target.Close();

            return packets;
        }

        public Dictionary<string, string> walk(UdpTarget target, string oid)
        {
            Dictionary<string, string> Output = new Dictionary<string, string>();
            // Define Oid that is the root of the MIB
            //  tree you wish to retrieve
            Oid rootOid = new Oid(oid); // ifDescr

            // This Oid represents last Oid returned by
            //  the SNMP agent
            Oid lastOid = (Oid)rootOid.Clone();

            // Pdu class used for all requests
            Pdu pdu = new Pdu(PduType.GetNext);

            if (useCache == true ) {
                Dictionary<string, string> data = getCache(target, oid);
                if (data.Count > 0 ) {
                    return data;
                }
            }

            // Loop through results
            while (lastOid != null)
            {
                // When Pdu class is first constructed, RequestId is set to a random value
                // that needs to be incremented on subsequent requests made using the
                // same instance of the Pdu class.
                if (pdu.RequestId != 0)
                {
                    pdu.RequestId += 1;
                }
                // Clear Oids from the Pdu class.
                pdu.VbList.Clear();
                // Initialize request PDU with the last retrieved Oid
                pdu.VbList.Add(lastOid);
                // Make SNMP request
                SnmpV1Packet result = (SnmpV1Packet)target.Request(pdu, param);
                // You should catch exceptions in the Request if using in real application.

                // If result is null then agent didn't reply or we couldn't parse the reply.
                if (result != null)
                {
                    // ErrorStatus other then 0 is an error returned by
                    // the Agent - see SnmpConstants for error definitions
                    if (result.Pdu.ErrorStatus != 0)
                    {
                        // agent reported an error with the request
                        Console.WriteLine("Error in SNMP reply. Error {0} index {1}",
                            result.Pdu.ErrorStatus,
                            result.Pdu.ErrorIndex);
                        lastOid = null;
                        break;
                    }
                    else
                    {
                        // Walk through returned variable bindings
                        foreach (Vb v in result.Pdu.VbList)
                        {
                            // Check that retrieved Oid is "child" of the root OID
                            if (rootOid.IsRootOf(v.Oid))
                            {
                                /*
                                  Console.WriteLine("{0} ({1}): {2}",
                                    v.Oid.ToString(),
                                    SnmpConstants.GetTypeName(v.Value.Type),
                                    v.Value.ToString());
                                 */
                                // keep the result
                                Output.Add(v.Oid.ToString(), v.Value.ToString());

                                lastOid = v.Oid;
                            }
                            else
                            {
                                // we have reached the end of the requested
                                // MIB tree. Set lastOid to null and exit loop
                                lastOid = null;
                            }
                        }
                    }
                }
                else
                {
                    Console.WriteLine("No response received from SNMP agent.");
                }
            }

            if (useCache == true || overrideCache == true ) {
                setCache(target, oid, Output);
            }
            return Output;
        }

 public static void GetTable()
 {
     Dictionary<String, Dictionary<uint, AsnType>> result = new Dictionary<String, Dictionary<uint, AsnType>>();
     // Not every row has a value for every column so keep track of all columns available in the table
     List<uint> tableColumns = new List<uint>();
     // Prepare agent information
     AgentParameters param = new AgentParameters(SnmpVersion.Ver2, new OctetString("public"));
     IpAddress peer = new IpAddress("192.168.15.42");
     if (!peer.Valid)
     {
         Console.WriteLine("Unable to resolve name or error in address for peer: {0}", "");
         return;
     }
     UdpTarget target = new UdpTarget((IPAddress)peer);
     // This is the table OID supplied on the command line
     Oid startOid = new Oid("1.3.6.1.2.1.47.1.1.1");
     // Each table OID is followed by .1 for the entry OID. Add it to the table OID
     startOid.Add(1); // Add Entry OID to the end of the table OID
                      // Prepare the request PDU
     Pdu bulkPdu = Pdu.GetBulkPdu();
     bulkPdu.VbList.Add(startOid);
     // We don't need any NonRepeaters
     bulkPdu.NonRepeaters = 0;
     // Tune MaxRepetitions to the number best suited to retrive the data
     bulkPdu.MaxRepetitions = 100;
     // Current OID will keep track of the last retrieved OID and be used as
     //  indication that we have reached end of table
     Oid curOid = (Oid)startOid.Clone();
     // Keep looping through results until end of table
     while (startOid.IsRootOf(curOid))
     {
         SnmpPacket res = null;
         try
         {
             res = target.Request(bulkPdu, param);
         }
         catch (Exception ex)
         {
             Console.WriteLine("Request failed: {0}", ex.Message);
             target.Close();
             return;
         }
         // For GetBulk request response has to be version 2
         if (res.Version != SnmpVersion.Ver2)
         {
             Console.WriteLine("Received wrong SNMP version response packet.");
             target.Close();
             return;
         }
         // Check if there is an agent error returned in the reply
         if (res.Pdu.ErrorStatus != 0)
         {
             Console.WriteLine("SNMP agent returned error {0} for request Vb index {1}",
                               res.Pdu.ErrorStatus, res.Pdu.ErrorIndex);
             target.Close();
             return;
         }
         // Go through the VbList and check all replies
         foreach (Vb v in res.Pdu.VbList)
         {
             curOid = (Oid)v.Oid.Clone();
             // VbList could contain items that are past the end of the requested table.
             // Make sure we are dealing with an OID that is part of the table
             if (startOid.IsRootOf(v.Oid))
             {
                 // Get child Id's from the OID (past the table.entry sequence)
                 uint[] childOids = Oid.GetChildIdentifiers(startOid, v.Oid);
                 // Get the value instance and converted it to a dotted decimal
                 //  string to use as key in result dictionary
                 uint[] instance = new uint[childOids.Length - 1];
                 Array.Copy(childOids, 1, instance, 0, childOids.Length - 1);
                 String strInst = InstanceToString(instance);
                 // Column id is the first value past <table oid>.entry in the response OID
                 uint column = childOids[0];
                 if (!tableColumns.Contains(column))
                     tableColumns.Add(column);
                 if (result.ContainsKey(strInst))
                 {
                     result[strInst][column] = (AsnType)v.Value.Clone();
                 }
                 else
                 {
                     result[strInst] = new Dictionary<uint, AsnType>();
                     result[strInst][column] = (AsnType)v.Value.Clone();
                 }
             }
             else
             {
                 // We've reached the end of the table. No point continuing the loop
                 break;
             }
         }
         // If last received OID is within the table, build next request
         if (startOid.IsRootOf(curOid))
         {
             bulkPdu.VbList.Clear();
             bulkPdu.VbList.Add(curOid);
             bulkPdu.NonRepeaters = 0;
             bulkPdu.MaxRepetitions = 100;
         }
//.........这里部分代码省略.........

        private void button11_Click(object sender, EventArgs e)
        {
            //SnmpTest snt = new SnmpTest(tbAddress.Text, "public", ".1.3.6.1.4.1.38446");
            //string[] t=  {".1.3.6.1.4.1.38446"};
            //snt.Test();

            


            OctetString community = new OctetString("public");
            AgentParameters param = new AgentParameters(community);
            param.Version = SnmpVersion.Ver2;
            IpAddress agent = new IpAddress("192.168.1.120");
            UdpTarget target = new UdpTarget((IPAddress)agent, 161, 2000, 1);

            Pdu pdu2 = new Pdu(PduType.GetBulk);
            pdu2.VbList.Add(".1.3.6.1.4.1.38446.1.1.2.1.13");

            SnmpV2Packet result2 = (SnmpV2Packet)target.Request(pdu2, param);

            int i=result2.Pdu.VbCount;
            
            string str= SnmpConstants.GetTypeName(result2.Pdu.VbList[0].Value.Type);
            string str2 = result2.Pdu.VbList[0].Value.ToString();
            return;











            // Define Oid that is the root of the MIB
            //  tree you wish to retrieve
            Oid rootOid = new Oid(".1.3.6.1.4.1.38446.1.5.9.1.9"); // ifDescr

            // This Oid represents last Oid returned by
            //  the SNMP agent
            Oid lastOid = (Oid)rootOid.Clone();

            // Pdu class used for all requests
            Pdu pdu = new Pdu(PduType.GetBulk);

            // In this example, set NonRepeaters value to 0
            pdu.NonRepeaters = 0;
            // MaxRepetitions tells the agent how many Oid/Value pairs to return
            // in the response.
            pdu.MaxRepetitions = 5;

            // Loop through results
            while (lastOid != null)
            {
                // When Pdu class is first constructed, RequestId is set to 0
                // and during encoding id will be set to the random value
                // for subsequent requests, id will be set to a value that
                // needs to be incremented to have unique request ids for each
                // packet
                if (pdu.RequestId != 0)
                {
                    pdu.RequestId += 1;
                }
                // Clear Oids from the Pdu class.
                pdu.VbList.Clear();
                // Initialize request PDU with the last retrieved Oid
                pdu.VbList.Add(lastOid);
                // Make SNMP request
                SnmpV2Packet result = (SnmpV2Packet)target.Request(pdu, param);
                // You should catch exceptions in the Request if using in real application.

                // If result is null then agent didn't reply or we couldn't parse the reply.
                if (result != null)
                {
                    // ErrorStatus other then 0 is an error returned by 
                    // the Agent - see SnmpConstants for error definitions
                    if (result.Pdu.ErrorStatus != 0)
                    {
                        // agent reported an error with the request
                        Console.WriteLine("Error in SNMP reply. Error {0} index {1}",
                            result.Pdu.ErrorStatus,
                            result.Pdu.ErrorIndex);
                        lastOid = null;
                        break;
                    }
                    else
                    {
                        // Walk through returned variable bindings
                        foreach (Vb v in result.Pdu.VbList)
                        {
                            // Check that retrieved Oid is "child" of the root OID
                            if (rootOid.IsRootOf(v.Oid))
                            {
                                Console.WriteLine("{0} ({1}): {2}",
                                    v.Oid.ToString(),
                                    SnmpConstants.GetTypeName(v.Value.Type),
                                    v.Value.ToString());
                                lastOid = v.Oid;
//.........这里部分代码省略.........

    /// <summary>
    /// Will get the rest of the variables, parts and percentages
    /// </summary>
    private Dictionary<String, String> getData()
    {
        Dictionary<String, String> dictionary = new Dictionary<String, String>();
        OctetString community = new OctetString( "public" );
        AgentParameters param = new AgentParameters( community );
        param.Version = SnmpVersion.Ver1;
        IpAddress agent = new IpAddress( printerName );

        UdpTarget target = new UdpTarget( (System.Net.IPAddress)agent, 161, 2000, 1 );
        Oid rootOid = new Oid( printerOID ); // ifDescr
        Oid lastOid = (Oid)rootOid.Clone();
        Pdu pdu = new Pdu( PduType.GetNext );

        while ( lastOid != null )
        {
            // When Pdu class is first constructed, RequestId is set to a random value
            // that needs to be incremented on subsequent requests made using the
            // same instance of the Pdu class.
            if ( pdu.RequestId != 0 )
            {
                pdu.RequestId += 1;
            }
            // Clear Oids from the Pdu class.
            pdu.VbList.Clear();
            // Initialize request PDU with the last retrieved Oid
            pdu.VbList.Add( lastOid );
            // Make SNMP request
            SnmpV1Packet result = null;
            try
            {
                result = (SnmpV1Packet)target.Request( pdu, param );
            }
            catch
            {
                return null;
            }

            // If result is null then agent didn't reply or we couldn't parse the reply.
            if ( result != null )
            {
                // ErrorStatus other then 0 is an error returned by
                // the Agent - see SnmpConstants for error definitions
                if ( result.Pdu.ErrorStatus != 0 )
                {
                    // agent reported an error with the request
                    Console.WriteLine( "Error in SNMP reply. Error {0} index {1}",
                        result.Pdu.ErrorStatus,
                        result.Pdu.ErrorIndex );
                    lastOid = null;
                    break;
                }
                else
                {
                    // Walk through returned variable bindings
                    foreach ( Vb v in result.Pdu.VbList )
                    {
                        // Check that retrieved Oid is "child" of the root OID
                        if ( rootOid.IsRootOf( v.Oid ) )
                        {
                            dictionary.Add( v.Oid.ToString(), v.Value.ToString() );
                            lastOid = v.Oid;
                        }
                        else
                        {
                            lastOid = null;
                        }
                    }
                }
            }
            else
            {
                Console.WriteLine( "No response received from SNMP agent." );
            }
        }
        target.Close();

        return dictionary;
    }

        public Tabela pobierzTabele()
        {
            /*! 
		     *Pobiera tabele SNMP.
             */
            Tabela tabela1 = new Tabela();
            AgentParameters param = new AgentParameters(SnmpVersion.Ver2, new OctetString(community));
            IpAddress peer = new IpAddress(host);
            if (!peer.Valid)
            {
                Console.WriteLine("Zły adres.");
                //return false;
            }
            UdpTarget target = new UdpTarget((IPAddress)peer);
            Oid startOid = new Oid("1.3.6.1.2.1.6.13");
            startOid.Add(1);
            Pdu bulkPdu = Pdu.GetBulkPdu();
            bulkPdu.VbList.Add(startOid);
            bulkPdu.NonRepeaters = 0;
            bulkPdu.MaxRepetitions = 100;
            Oid curOid = (Oid)startOid.Clone();
            while (startOid.IsRootOf(curOid))
            {
                SnmpPacket res = null;
                try
                {
                    res = target.Request(bulkPdu, param);
                }
                catch (Exception ex)
                {
                    Console.WriteLine("Zapytanie nieudane {0}", ex.Message);
                    target.Close();
                    //return false;
                }
                if (res.Version != SnmpVersion.Ver2)
                {
                    Console.WriteLine("Otrzymano inną wersję SNMP w odpowiedzi.");
                    target.Close();
                    //return false;
                }
                if (res.Pdu.ErrorStatus != 0)
                {
                    Console.WriteLine("SNMP agent zwrócił błąd {0} dla zapytania {1}", res.Pdu.ErrorStatus, res.Pdu.ErrorIndex);
                    target.Close();
                    //return false;
                }
                foreach (Vb v in res.Pdu.VbList)
                {
                    curOid = (Oid)v.Oid.Clone();
                    if (startOid.IsRootOf(v.Oid))
                    {
                        uint[] childOids = Oid.GetChildIdentifiers(startOid, v.Oid);
                        uint[] instance = new uint[childOids.Length - 1];
                        Array.Copy(childOids, 1, instance, 0, childOids.Length - 1);
                        String strInst = InstanceToString(instance);
                        uint column = childOids[0];
                        if (!tabelaKolumn.Contains(column))
                            tabelaKolumn.Add(column);
                        if (slownikRezultatu.ContainsKey(strInst))
                        {
                            slownikRezultatu[strInst][column] = (AsnType)v.Value.Clone();
                        }
                        else {
                            slownikRezultatu[strInst] = new Dictionary<uint, AsnType>();
                            slownikRezultatu[strInst][column] = (AsnType)v.Value.Clone();
                        }
                    }
                    else {
                        break;
                    }
                }
                if (startOid.IsRootOf(curOid))
                {
                    bulkPdu.VbList.Clear();
                    bulkPdu.VbList.Add(curOid);
                    bulkPdu.NonRepeaters = 0;
                    bulkPdu.MaxRepetitions = 100;
                }
            }
            target.Close();

            if (slownikRezultatu.Count <= 0)
            {
                //Console.WriteLine("Żadnych rezlutatów nie zwrócono");
                //return false;
            }
            else {
                //return true;
            }

            /*UFAM W TABELE, ŻE SŁOWNIK NIE ODWRÓCI KOLEJNOŚCI I WALĘ NA OŚLEP KOLEJNE WARTOŚCI*/
            foreach (KeyValuePair<string, Dictionary<uint, AsnType>> kvp in slownikRezultatu)
            {
                int i = 0;
                tabela1.tcpAddress.Add(kvp.Key);
                foreach (uint kolumna in tabelaKolumn)
                {
                    if (kvp.Value.ContainsKey(kolumna))
                    {
                        if (i == 0)
//.........这里部分代码省略.........

        public void pobierzTabeleDoUsuniecia()
        {
            /*! 
		     *Pobiera tabele SNMP.
             */
            Dictionary<String, Dictionary<uint, AsnType>> tabela_rezultat = new Dictionary<string, Dictionary<uint, AsnType>>();
            List<uint> tabeleKolumy = new List<uint>();
            AgentParameters param = new AgentParameters(SnmpVersion.Ver2, new OctetString(community));
            IpAddress peer = new IpAddress(host);
            if (!peer.Valid)
            {
                Console.WriteLine("Zły adres.");
                return;
            }

            UdpTarget target = new UdpTarget((IPAddress)peer);
            Oid startOid = new Oid("1.3.6.1.2.1.6.13");
            startOid.Add(1);

            //przygotowanie zapytania
            Pdu bulkPdu = Pdu.GetBulkPdu();
            bulkPdu.VbList.Add(startOid);
            bulkPdu.NonRepeaters = 0;
            bulkPdu.MaxRepetitions = 100;
            Oid curOid = (Oid)startOid.Clone();
            while (startOid.IsRootOf(curOid))
            {
                SnmpPacket res = null;
                try
                {
                    res = target.Request(bulkPdu, param);
                }
                catch (Exception ex)
                {
                    Console.WriteLine("Zapytanie nieudane {0}", ex.Message);
                    target.Close();
                    return;
                }
                if (res.Version != SnmpVersion.Ver2)
                {
                    Console.WriteLine("Received wrong SNMP version response packet.");
                    target.Close();
                    return;
                }
                if (res.Pdu.ErrorStatus != 0)
                {
                    Console.WriteLine("SNMP agent zwrócił błąd {0} dla zapytania {1}", res.Pdu.ErrorStatus, res.Pdu.ErrorIndex);
                    target.Close();
                    return;
                }
                foreach (Vb v in res.Pdu.VbList)
                {
                    curOid = (Oid)v.Oid.Clone();
                    if (startOid.IsRootOf(v.Oid))
                    {
                        uint[] childOids = Oid.GetChildIdentifiers(startOid, v.Oid);
                        uint[] instance = new uint[childOids.Length - 1];
                        Array.Copy(childOids, 1, instance, 0, childOids.Length - 1);
                        String strInst = InstanceToString(instance);
                        uint column = childOids[0];
                        if (!tabeleKolumy.Contains(column))
                            tabeleKolumy.Add(column);
                        if (tabela_rezultat.ContainsKey(strInst))
                        {
                            tabela_rezultat[strInst][column] = (AsnType)v.Value.Clone();
                        }
                        else
                        {
                            tabela_rezultat[strInst] = new Dictionary<uint, AsnType>();
                            tabela_rezultat[strInst][column] = (AsnType)v.Value.Clone();
                        }
                    }
                    else
                    {
                        break; //bo koniec tabeli ;)
                    }
                }
                if (startOid.IsRootOf(curOid))
                {
                    bulkPdu.VbList.Clear();
                    bulkPdu.VbList.Add(curOid);
                    bulkPdu.NonRepeaters = 0;
                    bulkPdu.MaxRepetitions = 100;
                }
                target.Close();
                if (tabela_rezultat.Count <= 0)
                {
                    Console.WriteLine("Żadnych rezlutatów nie zwrócono");
                }
                else
                {
                    Console.WriteLine("Instance");
                    foreach (uint column in tabeleKolumy)
                    {
                        Console.Write("\tColumn id {0}", column);
                    }
                    Console.WriteLine("");
                    foreach (KeyValuePair<string, Dictionary<uint, AsnType>> kvp in tabela_rezultat)
                    {
                        Console.Write("{0}", kvp.Key);
//.........这里部分代码省略.........

        static void remoteCall(string[] args)
        {
            // SNMP community name
            OctetString community = new OctetString("public");

            // Define agent parameters class
            AgentParameters param = new AgentParameters(community);
            // Set SNMP version to 2 (GET-BULK only works with SNMP ver 2 and 3)
            param.Version = SnmpVersion.Ver2;
            // Construct the agent address object
            // IpAddress class is easy to use here because
            //  it will try to resolve constructor parameter if it doesn't
            //  parse to an IP address
            IpAddress agent = new IpAddress("127.0.0.1");

            // Construct target
            UdpTarget target = new UdpTarget((IPAddress)agent, 161, 2000, 1);

            // Define Oid that is the root of the MIB
            //  tree you wish to retrieve
            Oid rootOid = new Oid("1.3.6.1.2.1.2.2.1.2"); // ifDescr

            // This Oid represents last Oid returned by
            //  the SNMP agent
            Oid lastOid = (Oid)rootOid.Clone();

            // Pdu class used for all requests
            Pdu pdu = new Pdu(PduType.GetBulk);

            // In this example, set NonRepeaters value to 0
            pdu.NonRepeaters = 0;
            // MaxRepetitions tells the agent how many Oid/Value pairs to return
            // in the response.
            pdu.MaxRepetitions = 5;

            // Loop through results
            while (lastOid != null)
            {
                // When Pdu class is first constructed, RequestId is set to 0
                // and during encoding id will be set to the random value
                // for subsequent requests, id will be set to a value that
                // needs to be incremented to have unique request ids for each
                // packet
                if (pdu.RequestId != 0)
                {
                    pdu.RequestId += 1;
                }
                // Clear Oids from the Pdu class.
                pdu.VbList.Clear();
                // Initialize request PDU with the last retrieved Oid
                pdu.VbList.Add(lastOid);
                // Make SNMP request
                SnmpV2Packet result = (SnmpV2Packet)target.Request(pdu, param);
                // You should catch exceptions in the Request if using in real application.

                // If result is null then agent didn't reply or we couldn't parse the reply.
                if (result != null)
                {
                    // ErrorStatus other then 0 is an error returned by
                    // the Agent - see SnmpConstants for error definitions
                    if (result.Pdu.ErrorStatus != 0)
                    {
                        // agent reported an error with the request
                        Console.WriteLine("Error in SNMP reply. Error {0} index {1}",
                            result.Pdu.ErrorStatus,
                            result.Pdu.ErrorIndex);
                        lastOid = null;
                        break;
                    }
                    else
                    {
                        // Walk through returned variable bindings
                        foreach (Vb v in result.Pdu.VbList)
                        {
                            // Check that retrieved Oid is "child" of the root OID
                            if (rootOid.IsRootOf(v.Oid))
                            {
                                Console.WriteLine("{0} ({1}): {2}",
                                    v.Oid.ToString(),
                                    SnmpConstants.GetTypeName(v.Value.Type),
                                    v.Value.ToString());
                                if (v.Value.Type == SnmpConstants.SMI_ENDOFMIBVIEW)
                                    lastOid = null;
                                else
                                    lastOid = v.Oid;
                            }
                            else
                            {
                                // we have reached the end of the requested
                                // MIB tree. Set lastOid to null and exit loop
                                lastOid = null;
                            }
                        }
                    }
                }
                else
                {
                    Console.WriteLine("No response received from SNMP agent.");
                }
            }
//.........这里部分代码省略.........

        /// <summary>SNMP WALK operation</summary>
        /// <remarks>
        /// When using SNMP version 1, walk is performed using GET-NEXT calls. When using SNMP version 2, 
        /// walk is performed using GET-BULK calls.
        /// </remarks>
        /// <example>Example SNMP walk operation using SNMP version 1:
        /// <code>
        /// String snmpAgent = "10.10.10.1";
        /// String snmpCommunity = "private";
        /// SimpleSnmp snmp = new SimpleSnmp(snmpAgent, snmpCommunity);
        /// Dictionary&lt;Oid, AsnType&gt; result = snmp.Walk(SnmpVersion.Ver1, "1.3.6.1.2.1.1");
        /// if( result == null ) {
        ///   Console.WriteLine("Request failed.");
        /// } else {
        /// foreach (KeyValuePair&lt;Oid, AsnType&gt; entry in result)
        /// {
        ///   Console.WriteLine("{0} = {1}: {2}", entry.Key.ToString(), SnmpConstants.GetTypeName(entry.Value.Type),
        ///     entry.Value.ToString());
        /// }
        /// </code>
        /// Will return:
        /// <code>
        /// 1.3.6.1.2.1.1.1.0 = OctetString: "Dual core Intel notebook"
        /// 1.3.6.1.2.1.1.2.0 = ObjectId: 1.3.6.1.9.233233.1.1
        /// 1.3.6.1.2.1.1.3.0 = TimeTicks: 0d 0h 0m 1s 420ms
        /// 1.3.6.1.2.1.1.4.0 = OctetString: "[email protected]"
        /// 1.3.6.1.2.1.1.5.0 = OctetString: "milans-nbook"
        /// 1.3.6.1.2.1.1.6.0 = OctetString: "Developer home"
        /// 1.3.6.1.2.1.1.8.0 = TimeTicks: 0d 0h 0m 0s 10ms
        /// </code>
        /// 
        /// To use SNMP version 2, change snmp.Set() method call first parameter to SnmpVersion.Ver2.
        /// </example>
        /// <param name="version">SNMP protocol version. Acceptable values are SnmpVersion.Ver1 and 
        /// SnmpVersion.Ver2</param>
        /// <param name="rootOid">OID to start WALK operation from. Only child OIDs of the rootOid will be
        /// retrieved and returned</param>
        /// <param name="tryGetBulk">this param is used to use get bulk on V2 requests</param>
        /// <returns>Oid => AsnType value mappings on success, empty dictionary if no data was found or
        /// null on error</returns>
        public Dictionary<Oid, AsnType> Walk(bool tryGetBulk, SnmpVersion version, string rootOid)
        {
            if (!Valid)
            {
                if (!_suppressExceptions)
                {
                    throw new SnmpException("SimpleSnmp class is not valid.");
                }
                return null;
            }
            // function only works on SNMP version 1 and SNMP version 2 requests
            if (version != SnmpVersion.Ver1 && version != SnmpVersion.Ver2)
            {
                if (!_suppressExceptions)
                {
                    throw new SnmpInvalidVersionException("SimpleSnmp support SNMP version 1 and 2 only.");
                }
                return null;
            }
            if (rootOid.Length < 2)
            {
                if (!_suppressExceptions)
                {
                    throw new SnmpException(SnmpException.InvalidOid, "RootOid is not a valid Oid");
                }
                return null;
            }
            Oid root = new Oid(rootOid);
            if (root.Length <= 0)
            {
                return null; // unable to parse root oid
            }
            Oid lastOid = (Oid)root.Clone();

            Dictionary<Oid, AsnType> result = new Dictionary<Oid, AsnType>();
            while (lastOid != null && root.IsRootOf(lastOid))
            {
                Dictionary<Oid, AsnType> val = null;
                if (version == SnmpVersion.Ver1)
                {
                    val = GetNext(version, new string[] { lastOid.ToString() });
                }
                else
                {
                    if (tryGetBulk == true)
                    {
                        val = GetBulk(new string[] { lastOid.ToString() });
                    }
                    else
                    {
                        val = GetNext(version, new string[] { lastOid.ToString() });
                    }
                }
                // check that we have a result
                if (val == null)
                {
                    // error of some sort happened. abort...
                    return null;
                }
                foreach (KeyValuePair<Oid, AsnType> entry in val)
//.........这里部分代码省略.........