为BeginReceive提供的字节

我的程序所做的是,在第一次接受连接时,服务器发送数据 客户端接收然后再次发送(数据大小不更改) 服务器接收到它,然后再次发送…循环继续…

当服务器第二次接收数据时,endReceive()返回的int;为0

虽然我已经找到了解决方案,但我不知道为什么这确实解决了问题

我在这里读到有个叫做“脏”缓冲器的东西:s

所以我所做的就是。

//added line
data = new byte[DataSize];

//now index works fine :s
int index = socket.endreceive(result);

以前我在重复使用 byte[] data 对于不更改其内容的发送和接收,数据发送全部为零。

它起作用了:)

在那里,msdn帮不了我,还是我错过了睡眠? MSDN Link

这是汇总代码

    private void OnSendCallBack(IAsyncResult result)
    {
        int id_client = (int)result.AsyncState;
        try
        {

            int index = clientInfo[id_client].client.EndSend(result);

            clientInfo[id_client].offsetSend += index;
            if (index == 0)
            {
                Console.WriteLine("Index == 0");
                return;
            }
            else if (clientInfo[id_client].offsetSend < DataSize)
            {
                clientInfo[id_client].dataToSend = DataSize - clientInfo[id_client].offsetSend;
                clientInfo[id_client].client.BeginSend(data, clientInfo[id_client].offsetSend, clientInfo[id_client].dataToSend, SocketFlags.None, RecieveCallBack, id_client);
            }
            else 
            {
                clientInfo[id_client].offsetSend = 0;
                clientInfo[id_client].dataToSend = DataSize;
                //*************************************
                data = new byte[DataSize]; // THIS IS THE PROBLEM HERE
                //*************************************
                clientInfo[id_client].client.BeginReceive(data, 0, data.Length, SocketFlags.None, RecieveCallBack, id_client);
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine("Send: " + ex.Message);
        }
    }

private void RecieveCallBack(IAsyncResult result)
    {
        int id_client = (int)result.AsyncState;

        try
        {

            int index = clientInfo[id_client].client.EndReceive(result);

            //byte[] buffer = new byte[DataSize];
            //int received = clientInfo[id_client].client.Receive(buffer);

            clientInfo[id_client].offsetRec += index;
            if (index == 0)
            {
                index = clientInfo[id_client].client.EndReceive(result);
                Console.WriteLine("Index == 0");
                return;
            }
            else if (clientInfo[id_client].offsetRec < DataSize && clientInfo[id_client].offsetRec != 0)
            {
                clientInfo[id_client].dataToReceive = DataSize - clientInfo[id_client].offsetRec;
                clientInfo[id_client].client.BeginReceive(data, clientInfo[id_client].offsetRec, clientInfo[id_client].dataToReceive, SocketFlags.None, RecieveCallBack, id_client);
            }
            else
            {
                clientInfo[id_client].offsetRec = 0;
                clientInfo[id_client].dataToReceive = DataSize;

                if (clientInfo[id_client].RunNumber < RounCount)
                {
                    clientInfo[id_client].RoundTripStat.EndSample();
                    clientInfo[id_client].RoundTripStat.BeginSample(); 
                    clientInfo[id_client].client.BeginSend(data, 0, data.Length, SocketFlags.None, OnSendCallBack, id_client); 
                }

                Close(id_client);
            }

        }
        catch (Exception ex)
        {
            Console.WriteLine("Server: " + ex.Message);
        }
    }

我提供了sendcallback和receive回调的代码,您可以看到一个asynch命令正在一次等待一个。