System.Object
   Dart.Sockets.DnsSlave
   Dart.Sockets.Echo
   Dart.Sockets.License
   Dart.Sockets.MxHostEntry
   Dart.Sockets.PingSlave
   Dart.Sockets.Proxy
   Dart.Sockets.Security
      Dart.Sockets.ClientSecurity
      Dart.Sockets.ServerSecurity
   Dart.Sockets.Segment
      Dart.Sockets.Data
         Dart.Sockets.Datagram
   Dart.Sockets.Session
      Dart.Sockets.TcpSession
   Dart.Sockets.SocketOption
      Dart.Sockets.TcpSocketOption
      Dart.Sockets.UdpSocketOption
   System.EventArgs
      Dart.Sockets.BaseEventArgs
      Dart.Sockets.ConnectionsChangedEventArgs
      Dart.Sockets.EchoEventArgs
      Dart.Sockets.ErrorEventArgs
      Dart.Sockets.UserStateEventArgs
         Dart.Sockets.DataEventArgs
   System.Exception
      Dart.Sockets.DartLicenseException
      System.ApplicationException
         Dart.Sockets.DataException
         Dart.Sockets.ProtocolException
   System.MarshalByRefObject
      System.ComponentModel.Component
         Dart.Sockets.ComponentBase
            Dart.Sockets.Dns
            Dart.Sockets.Ping
            Dart.Sockets.SocketBase
               Dart.Sockets.Server
               Dart.Sockets.TcpBase
                  Dart.Sockets.PtyBase
                     Dart.Sockets.Tcp
               Dart.Sockets.UdpBase
                  Dart.Sockets.Udp
   System.Net.EndPoint
      System.Net.IPEndPoint
         Dart.Sockets.IPEndPoint

Reference

Dart.Sockets Assembly