SharpSmpLib|字节必须包含4或16个元素-导致此错误的原因

Question

https://github.com/lextm/sharpsnmplib/blob/master/SharpSnmpLib/IP.cs

System.ArgumentException: bytes must contain 4 or 16 elements
at Lextm.SharpSnmpLib.IP..ctor(Tuple`2 length, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Int32 type, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Stream stream)
at Lextm.SharpSnmpLib.Sequence..ctor(Tuple`2 length, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Int32 type, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Stream stream)
at Lextm.SharpSnmpLib.Sequence..ctor(Tuple`2 length, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Int32 type, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Stream stream)
at Lextm.SharpSnmpLib.ResponsePdu..ctor(Tuple`2 length, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Int32 type, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Stream stream)
at Lextm.SharpSnmpLib.Sequence..ctor(Tuple`2 length, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Int32 type, Stream stream)
at Lextm.SharpSnmpLib.Messaging.MessageFactory.ParseMessage(Int32 first, Stream stream,            UserRegistry registry)
at Lextm.SharpSnmpLib.Messaging.MessageFactory.ParseMessages(Byte[] buffer, Int32 index, Int32  length, UserRegistry registry)
at Lextm.SharpSnmpLib.Messaging.SnmpMessageExtension.GetResponse(ISnmpMessage request, Int32   timeout, IPEndPoint receiver, UserRegistry registry, Socket udpSocket)
at Lextm.SharpSnmpLib.Messaging.SnmpMessageExtension.GetResponse(ISnmpMessage request, Int32 timeout, IPEndPoint receiver, Socket udpSocket)
at Lextm.SharpSnmpLib.Messaging.SnmpMessageExtension.GetResponse(ISnmpMessage request, Int32 timeout, IPEndPoint receiver)
at Lextm.SharpSnmpLib.Messaging.Messenger.BulkHasNext(VersionCode version, IPEndPoint endpoint,  OctetString community, Variable seed, Int32 timeout, Int32 maxRepetitions, IList`1& next,  IPrivacyProvider privacy, ISnmpMessage& report)
at Lextm.SharpSnmpLib.Messaging.Messenger.BulkWalk(VersionCode version, IPEndPoint endpoint, OctetString community, ObjectIdentifier table, IList`1 list, Int32 timeout, Int32 maxRepetitions, WalkMode mode, IPrivacyProvider privacy, ISnmpMessage report)
at Maprinter.snmpWalk..ctor(String IP, String ID, Int32 timeOut)

我使用这个库是为了从网络打印机中提取一些数据。到目前为止，一切都很好，大多数打印机都会给我返回我想要的数据。但是当我收到这个错误时，我没有从打印机收到任何东西，那么是什么原因导致了这个错误？

Messenger.BulkWalk(VersionCode.V2,
                                   new IPEndPoint(IPAddress.Parse("10.0.0.101"), 161),
                                   new OctetString("public"),
                                   new ObjectIdentifier("1.3.6.1"),
                                   result,
                                   timeOut,
                                   10,
                                   WalkMode.Default,
                                   null,
                                   null);

Answer 1

异常可能是由该设备上发送空IpAddress主体(0x40，0x00(的SNMP代理引起的。这违反了标准，因为结果应该是Null主体(0x05，0x00(。

IpAddress是在RFC2578中定义的，它严格地由4个字节组成。这就是为什么#SNMP检查4。针对16的检查是针对IPv6地址的，尽管它们实际上应该受到自定义约定的支持。

在您的情况下，选项可以是，

• 修复固件，以便发送正确的正文
• 修改#SNMP代码库(MIT/X11许可证(并满足您的需求