（转）C# :base的用法（冒号后面的base）

public abstract class HttpBasedTransport : ClientTransportBase
    {
        protected HttpBasedTransport(IHttpClient httpClient, string transportName)
            : base(httpClient, transportName)
        { }
    }

public abstract class ClientTransportBase : IClientTransport
    {
        private readonly IHttpClient _httpClient;
        private readonly string _transportName;
        private readonly TransportHelper _transportHelper;
        private readonly TransportAbortHandler _abortHandler;
        private bool _finished = false;

        private TransportInitializationHandler _initializationHandler;

        [SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Justification = "Disposed in the Dispose method.")]
        protected ClientTransportBase(IHttpClient httpClient, string transportName)
            : this(httpClient, transportName, new TransportHelper(), new TransportAbortHandler(httpClient, transportName))
        {
        }

        internal ClientTransportBase(IHttpClient httpClient, string transportName, TransportHelper transportHelper, TransportAbortHandler abortHandler)
        {
            if (httpClient == null)
            {
                throw new ArgumentNullException("httpClient");
            }

            if (string.IsNullOrWhiteSpace(transportName))
            {
                throw new ArgumentNullException("transportName");
            }

            Debug.Assert(transportHelper != null, "transportHelper is null");
            Debug.Assert(abortHandler != null, "abortHandler is null");

            _httpClient = httpClient;
            _transportName = transportName;
            _transportHelper = transportHelper;
            _abortHandler = abortHandler;
        }
    }