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Problems with Async Sockets C # Server

I applied the Server application for this publication here: http://www.codeguru.com/csharp/csharp/cs_network/sockets/article.php/c8781#Client1

Amount: I use async Sockets ala BeginAccept (..), BeginReceive (..). My server is capable of handling multi-tenant clients, and everything works fine until the client performs two or more synchronous send operations, without waiting for some time. The client does not receive any errors and therefore is not notified that the server is not receiving a second message! If the client waits approx. 100 ms after the first send operation, everything works fine. I thought that when I use TCP, I can guarantee that the server will receive a message. (Except that there is an exception)! Could you give me a solution to fix this.

Here are the WaitForData (..) and OnDataReceive (..) methods that I implemented on the server

public void WaitForData(MyClient client)
{
    try
    {
        if (pfnCallBack == null)
        {
            pfnCallBack = new AsyncCallback(OnDataReceived);
        }

        iarResult = client.Socket.BeginReceive(client.DataBuffer,
                                                0, client.DataBuffer.Length,
                                                SocketFlags.None,
                                                pfnCallBack,
                                                client);
    }
    catch (SocketException se)
    {
        MessageBox.Show("SocketException@WaitForData" + se.Message);
    }
}
public void OnDataReceived(IAsyncResult asyn)
{
    try
    {
        MyClient user= (MyClient)asyn.AsyncState;
        int iRx = user.Socket.EndReceive(asyn);

        byte[] receivedData = user.DataBuffer;

        MemoryStream memStream = new MemoryStream();
        BinaryFormatter binForm = new BinaryFormatter();
        memStream.Write(receivedData, 0, receivedData.Length);
        memStream.Seek(0, SeekOrigin.Begin);
        MyMessage msg = (MyMessage)binForm.Deserialize(memStream);

        switch (msg.Command)
        {
            case (MyMessage.MyCommand.ConnId):
                this.connId = (int) msg.MyObject;
                tsslConnStatus.Text += " | ID: " + connId.ToString();
            break;

            case (MyMessage.MyCommand.Text):
                MessageBox.Show(msg.MyObject.ToString());
                break;
        }
        WaitForData(server);
    }
    catch (ObjectDisposedException ode)
    {
        MessageBox.Show("ObjectDisposedException@OnReceiveData" + ode.Message);
    }
    catch (SocketException se)
    {
        MessageBox.Show("SocketException@OnReceiveData" + se.Message);
    }
}

CLIENT calls the synchronous SEND METWOD TWICE method or MORE! INSTANCEOF MyClient server

if (server.Socket.Connected)
{
    BinaryFormatter bf = new BinaryFormatter();
    MemoryStream ms = new MemoryStream();
    bf.Serialize(ms, message);
    MyMessage = new MyMessage(something);
    server.Socket.Send(ms.ToArray());
}

, , , , ! , , !

Thanx!

+3
1

TCP , . Read :

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Update

, .

:

var buffer = binaryFormmater.Serialize(myobj);
var length = buffer.Length;
networkStream.Send(length);
networkStream.Send(buffer, 0, buffer.Length);

:

var header = new buffer[4];
// TODO: You need to make sure that 4 bytes have been read.
networkStream.Read(header, 0, 4);
var length = BitConverter.ToInt32(buffer);

var readbuffer= new byte[65535];
var bytesLeft = length;
var messageStream = new MemoryStream();
while (bytesLeft > 0)
{
     var read = networkStream.Read(readbuffer, 0, bytesLeft);
     messageStream.Write(readbuffer, 0, read);
     bytesLeft -= read,
}

messageStream.Seek(0, SeekOrigin.Begin);
MyMessage msg = (MyMessage)binForm.Deserialize(messageStream);
+12

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