WCF技术内幕 第6章(6)

6.6 创建自定义通道

创建基类型

//Create base class
using System;
using System.ServiceModel.Channels;

namespace WCFChannelSample
{
    class DelegatorChannelBase<TShape> : ChannelBase
        where TShape : class, IChannel
    {
        private TShape _innerChannel; //引用堆栈中的下一个通道
        private string _source; //打印的字符

        protected TShape InnerChannel { get { return _innerChannel; } } //提供_innerChannel给继承类型

        protected DelegatorChannelBase(ChannelManagerBase channelManagerBase, TShape innerChannel, string source)
            : base(channelManagerBase)
        {
            if (innerChannel == null)
                throw new ArgumentNullException("DelegatorChannelBase requires a non-null channel.", "innerChannel");

            _source = string.Format("{0} CHANNEL STATE CHANGE: DelegatorChannelBase", source);
            _innerChannel = innerChannel;
        }

        //IChannel实现
        public override T GetProperty<T>()
        {
            return this.InnerChannel.GetProperty<T>();
        }

        #region CommunicationObject Members
        protected override void OnAbort()
        {
            Console.WriteLine("Abort:" + _source);
            this.InnerChannel.Abort();
        }

        protected override IAsyncResult OnBeginClose(TimeSpan timeout, AsyncCallback callback, object state)
        {
            Console.WriteLine("BeginClose:" + _source);
            return this.InnerChannel.BeginClose(timeout, callback, state);
        }

        protected override IAsyncResult OnBeginOpen(TimeSpan timeout, AsyncCallback callback, object state)
        {
            Console.WriteLine("BeginOpen:" + _source);
            return this.InnerChannel.BeginOpen(timeout, callback, state);
        }

        protected override void OnClose(TimeSpan timeout)
        {
            Console.WriteLine("Close:" + _source);
            this.InnerChannel.Close(timeout);
        }

        protected override void OnEndClose(IAsyncResult result)
        {
            Console.WriteLine("EndClose:" + _source);
            this.InnerChannel.EndClose(result);
        }

        protected override void OnEndOpen(IAsyncResult result)
        {
            Console.WriteLine("EndOpen:" + _source);
            this.InnerChannel.EndOpen(result);
        }

        protected override void OnOpen(TimeSpan timeout)
        {
            Console.WriteLine("Open:" + _source);
            this.InnerChannel.Open(timeout);
        }
        #endregion
    }
}

//数据报发送通道
using System.ServiceModel.Channels;

namespace WCFChannelSample
{
    class DelegatorInputChannel<TShape> : DelegatorChannelBase<TShape>, IInputChannel
        where TShape : class, IInputChannel
    {
        internal DelegatorInputChannel(ChannelManagerBase channelManagerBase, TShape innerChannel, string source)
            : base(channelManagerBase, innerChannel, source) { }
        ...
    }
}

数据报接收会话通道

//数据报接收会话通道
using System.ServiceModel.Channels;

namespace WCFChannelSample
{
    class DelegatorOutputSessionChannel<TShape> : DelegatorChannelBase<TShape>, IOutputSessionChannel
        where TShape : class, IOutputSessionChannel
    {
        internal DelegatorOutputSessionChannel(ChannelManagerBase channelManagerBase, TShape innerChannel, string source)
            : base(channelManagerBase, innerChannel, source) { }
        ...
    }
}