c#網路通訊架構networkcomms核心解析之九 自訂處理方法的運行機制

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本文基於networkcomms2.3.1開源版本  gplv3協議

我們自己寫的處理方法都稱之為自訂處理方法

比如，我們在伺服器上寫的與登陸相關的處理方法：

NetworkComms.AppendGlobalIncomingPacketHandler<LoginContract>("ReqLogin", IncomingLoginRequest);

   private void IncomingLoginRequest(PacketHeader header, Connection connection, LoginContract loginContract)        {            try            {                string resMsg="";                //為了簡單，這裡不調用資料庫，而是類比一下登入                if (loginContract.UserID == "1000" && loginContract.PassWord == "123")                    resMsg = "登入成功";                else                    resMsg = "使用者名稱密碼錯誤";                //把返回結果寫入到契約類中，後面返回給用戶端                ResMsgContract contract = new ResMsgContract();                contract.Message = resMsg;                 connection.SendObject("ResLogin", contract);            }            catch (Exception ex)            {                           }        }

通過以上的寫法，當伺服器器收到訊息類型為“ReqLogin"的訊息時，會自動擷取到相關的處理方法。

我們看一下背後的運行機制。

首先看註冊語句：

NetworkComms.AppendGlobalIncomingPacketHandler<LoginContract>("ReqLogin", IncomingLoginRequest);

AppendGlobalIncomingPacketHandler（）方法，把訊息類型”ReqLogin"和處理方法“INcomingLoginRequest"添加到NetworkComms靜態類的字典中：

在AppendGlobalIncomingPacketHander<T>方法中 ，我們的處理方法 IncomingLoginRequest 與 PacketHandlerCallBackDelegate<T>參數相對應。

來看一下PacketHandlerCallBackDelegate的定義

      public delegate void PacketHandlerCallBackDelegate<T>(PacketHeader packetHeader, Connection connection, T incomingObject);

 

AppendGlobalIncomingPacketHandler（）方法如下：

    public static void AppendGlobalIncomingPacketHandler<T>(string packetTypeStr, PacketHandlerCallBackDelegate<T> packetHandlerDelgatePointer)        {            if (packetTypeStr == null) throw new ArgumentNullException("packetTypeStr", "Provided packetType string cannot be null.");            if (packetHandlerDelgatePointer == null) throw new ArgumentNullException("packetHandlerDelgatePointer", "Provided PacketHandlerCallBackDelegate<T> cannot be null.");            if (sendReceiveOptions == null) throw new ArgumentNullException("sendReceiveOptions", "Provided SendReceiveOptions cannot be null.");            lock (globalDictAndDelegateLocker)            {                if (globalIncomingPacketUnwrappers.ContainsKey(packetTypeStr))                {                    //Make sure if we already have an existing entry that it matches with the provided                    if (!globalIncomingPacketUnwrappers[packetTypeStr].Options.OptionsCompatible(sendReceiveOptions))                        throw new PacketHandlerException("The proivded SendReceiveOptions are not compatible with existing SendReceiveOptions already specified for this packetTypeStr.");                }                else                    globalIncomingPacketUnwrappers.Add(packetTypeStr, new PacketTypeUnwrapper(packetTypeStr, sendReceiveOptions));                                //Ad the handler to the list                if (globalIncomingPacketHandlers.ContainsKey(packetTypeStr))                {                    //Make sure we avoid duplicates                    PacketTypeHandlerDelegateWrapper<T> toCompareDelegate = new PacketTypeHandlerDelegateWrapper<T>(packetHandlerDelgatePointer);                    bool delegateAlreadyExists = false;                    foreach (var handler in globalIncomingPacketHandlers[packetTypeStr])                    {                        if (handler == toCompareDelegate)                        {                            delegateAlreadyExists = true;                            break;                        }                    }                                                            if (delegateAlreadyExists)                        throw new PacketHandlerException("This specific packet handler delegate already exists for the provided packetTypeStr.");                    //把處理方法添加到相關字典中                    globalIncomingPacketHandlers[packetTypeStr].Add(new PacketTypeHandlerDelegateWrapper<T>(packetHandlerDelgatePointer));                }                else                    globalIncomingPacketHandlers.Add(packetTypeStr, new List<IPacketTypeHandlerDelegateWrapper>() { new PacketTypeHandlerDelegateWrapper<T>(packetHandlerDelgatePointer) });                if (LoggingEnabled) logger.Info("Added incoming packetHandler for ‘" + packetTypeStr + "‘ packetType.");            }        }

字典：

        static Dictionary<string, List<IPacketTypeHandlerDelegateWrapper>> globalIncomingPacketHandlers = new Dictionary<string, List<IPacketTypeHandlerDelegateWrapper>>();

 

我們看到上面有一句：

 PacketTypeHandlerDelegateWrapper<T> toCompareDelegate = new PacketTypeHandlerDelegateWrapper<T>(packetHandlerDelgatePointer);

看一下PacketTypeHandlerDelegateWrapper類，此類把處理方法作為參數。

我們看一下此類：

class PacketTypeHandlerDelegateWrapper<T> : IPacketTypeHandlerDelegateWrapper    {        NetworkComms.PacketHandlerCallBackDelegate<T> innerDelegate;        public PacketTypeHandlerDelegateWrapper(NetworkComms.PacketHandlerCallBackDelegate<T> packetHandlerDelegate)        {            this.innerDelegate = packetHandlerDelegate;        }        public object DeSerialize(MemoryStream incomingBytes, SendReceiveOptions options)        {            if (incomingBytes == null) return null;            //if (incomingBytes == null || incomingBytes.Length == 0) return null;            else            //{                //if (options.DataSerializer == null)                //    throw new ArgumentNullException("options", "The provided options.DataSerializer was null. Cannot continue with deserialise.");                return options.DataSerializer.DeserialiseDataObject<T>(incomingBytes, options.DataProcessors, options.Options);            //}        }        public void Process(PacketHeader packetHeader, Connection connection, object obj)        {            innerDelegate(packetHeader, connection, (obj == null ? default(T) : (T)obj));        }        public bool Equals(IPacketTypeHandlerDelegateWrapper other)        {            if (innerDelegate == (other as PacketTypeHandlerDelegateWrapper<T>).innerDelegate)                return true;            else                return false;        }        public bool EqualsDelegate(Delegate other)        {            return other as NetworkComms.PacketHandlerCallBackDelegate<T> == innerDelegate;        }    }

 

感覺這一章寫的不太清楚，水平有限，您可以自行閱讀一下networkcomms2.3.1開源版本的原始碼，擷取會看的比較清晰：）

www.cnblogs.com/networkcomms

www.networkcomms.cn

c#網路通訊架構networkcomms核心解析之九 自訂處理方法的運行機制