/// <summary>
        /// 异步发送
        /// </summary>
        /// <param name="buffer">字节数组</param>
        /// <param name="offset">起始偏移量</param>
        /// <param name="size">字节数</param>
        public void Write(Byte[] buffer, Int32 offset, Int32 size)
        {
            // 用户定义对象
            AsyncWriteStateObject State = new AsyncWriteStateObject
            {   // 将事件状态设置为非终止状态,导致线程阻止
                eventDone = new ManualResetEvent(false),
                stream    = Stream,
                exception = null,
            };

            Byte[] BytesArray;
            Int32  Length = size + 4;   // 加入4字节长度信息后的总长度

            BytesArray = new Byte[Length];
            Array.Copy(BitConverter.GetBytes(Length), BytesArray, 4);
            Array.Copy(buffer, offset, BytesArray, 4, size);

            // 写入加长度信息头的数据
            Stream.BeginWrite(BytesArray, 0, BytesArray.Length, new AsyncCallback(AsyncWriteCallback), State);

            // 等待操作完成信号
            if (State.eventDone.WaitOne(Stream.WriteTimeout, false))
            {   // 接收到信号
                if (State.exception != null)
                {
                    throw State.exception;
                }
            }
            else
            {   // 超时异常
                throw new TimeoutException();
            }
        }
        /// <summary>
        /// 异步写入回调函数
        /// </summary>
        /// <param name="ar">异步操作结果</param>
        private static void AsyncWriteCallback(IAsyncResult ar)
        {
            AsyncWriteStateObject State = ar.AsyncState as AsyncWriteStateObject;

            try
            {   // 异步写入结束
                State.stream.EndWrite(ar);
            }

            catch (Exception e)
            {   // 异步连接异常
                State.exception = e;
            }

            finally
            {   // 将事件状态设置为终止状态,线程继续
                State.eventDone.Set();
            }
        }
        /// <summary>  
        /// 异步发送  
        /// </summary>  
        /// <param name="buffer">字节数组</param>  
        /// <param name="offset">起始偏移量</param>  
        /// <param name="size">字节数</param>  
        public void Write(Byte[] buffer, Int32 offset, Int32 size)
        {
            // 用户定义对象
            AsyncWriteStateObject State = new AsyncWriteStateObject
            {   // 将事件状态设置为非终止状态,导致线程阻止
                eventDone = new ManualResetEvent(false),
                stream = Stream,
                exception = null,
            };

            Byte[] BytesArray;
            Int32 Length = size + 4;    // 加入4字节长度信息后的总长度
            BytesArray = new Byte[Length];
            Array.Copy(BitConverter.GetBytes(Length), BytesArray, 4);
            Array.Copy(buffer, offset, BytesArray, 4, size);

            // 写入加长度信息头的数据
            Stream.BeginWrite(BytesArray, 0, BytesArray.Length, new AsyncCallback(AsyncWriteCallback), State);

            // 等待操作完成信号
            if (State.eventDone.WaitOne(Stream.WriteTimeout, false))
            {   // 接收到信号
                if (State.exception != null) throw State.exception;
            }
            else
            {   // 超时异常
                throw new TimeoutException();
            }
        }